DESC:FIELD OF THE INVENTION:
The present invention relates to novel anti-cancer compounds, method of synthesizing said compounds and an anti-cancer pharmaceutical composition comprising said compounds. More particularly, the present invention relates to imidazole-pyridine, imidazole-pyrrole, and imidazole-indole compounds and a method of synthesizing said compounds and anti-cancer pharmaceutical composition along with excipients, adjuvants, fillers, pharmaceutically acceptable salts, etc.

BACKGROUND OF THE INVENTION:
Due to its high fatality rate and ten million annual fatalities, cancer poses a significant threat to global health. There are more than 100 different forms of cancer, but colon, lung, liver, and breast cancer are the most prevalent ones. Clinicians select from a range of drugs to treat breast cancer depending on the size, grade, aggressiveness, metastatic behavior, intrinsic molecular subtyping of the tumor, menopausal status, age, comorbidities, general health, and patient preferences. Surgery, radiation therapy, chemotherapy, targeted therapy, and immunotherapy are the most effective therapies for breast cancer and have been found to increase patient survival rates.
Chemotherapy, which involves treating tumor cells with various anticancer medications, has emerged as a key element of cancer treatment. The adjuvants now used in breast cancer treatment include anthracyclines, doxorubicin, epirubicin, taxanes, paclitaxel, docetaxel, fluorouracil, and cyclophosphamide. The three primary subtypes of breast cancer traditionally recognized are ER (estrogen receptor), PR (progesterone receptor), and HER-2 (human epithelial receptor 2). Hormone receptors are positive in more than 75% of breast cancer cases. However, very few effective therapeutic options are available for these subtypes. Consequently, creating more potent and less harmful chemotherapeutic drugs is urgently needed. By 2021, the FDA in the United States would have approved roughly 207 anti-cancer drugs.
However, a complete cure for cancer has not yet been developed. Chemotherapy frequently fails because it has harmful side effects, is ineffective, and is more expensive than other clinically relevant medications. In the discovery of anticancer drugs, lead molecules from heterocyclic compounds have been crucial. According to the FDA, 59% of medication molecules given official approval are heterocyclic compounds with at least one nitrogen atom. Numerous biological and pharmaceutical efforts to find new drug-design molecules are centered on nitrogen-containing substances. Additionally, because van der Waals forces of interaction, p-stacking interactions, and hydrogen bonds are weak bonds and are essential in biological systems, nitrogen-containing compounds are stable, easily interact with biological systems, and readily bond with DNA through hydrogen bonding. For synthesizing organic compounds and assessing biological activity, the creation of carbon-nitrogen (C-N) and carbon-carbon (C-C) bonds have become crucial priorities in recent years. Introducing a hetero unit at position two of the imidazole scaffold exhibits potential anticancer activity. These results show that imidazole ring modifications at the N-1 and C-2 positions have produced large chemical entities with enhanced anticancer activity. Furthermore, the importance of the phenyl rings at positions 4 and 5 is rising. Purines, essential components of DNA and RNA, form a ring like shape in imidazole. Imidazole acts on many important biological functions. Some amino acids, particularly histidine, possess an imidazole side chain. Histidine supplementation has improved the cytotoxic effects of numerous chemotherapy drugs on cancer cells in vitro. Histidine is being researched for potential medicinal purposes in addition to its role in human health. Imidazole-based scaffolds have a wide range of therapeutic properties, including antibacterial, antihistaminic, antitubercular, and anticancer activity, which makes them extremely interesting to pharmacological chemists. Lepidiline A and B are naturally occurring imidazolium salts with powerful cytotoxic properties against human cancer cell types. Additionally, possible chemosensitizer molecules that make cancer cells more sensitive to chemotherapeutic agents have been studied concerning imidazole scaffolds. In human cancer cell lines, imidazole and its derivatives may enhance the cytotoxic effects of a chemotherapeutic treatment. Numerous tumors treated using imidazole-containing medications, including Dacarbazine, Temozolomide, Etanidazole, Zoledronic acid, Azathioprine, Misonidazole, Pimonidazole, Mercaptopurine, Nilotinib, Tipifarnib, and Fadrozole, which have undergone clinical testing. Along with their effectiveness and safety in human clinical trials, these substances' possible side effects and toxicity must also be considered. In contrast, indole serves as an essential scaffold, is abundant in nature, is a component of the essential amino acid tryptophan, and has many vital bodily functions. It is impossible to synthesize it within the biological system because it is made from proteins. The conversion of tryptophan to niacin, a vitamin B3 crucial for energy production, DNA repair, and the maintenance of good skin, is one of the essential metabolic routes involving tryptophan. Niacin promotes DNA repair, which may help stop mutations and malignant cell development. Additionally, natural and synthesized indole molecules have a wide range of medical applications. Drug formulations contain both synthetic and natural substances, such as panobinostat, alectinib, osimertinib, semaxanib, sunitinib, and nintedanib, and their counterparts, such as vincristine, vinblastine, vinorelbine, vindesine, vinflunine, koumine, humantenine, and yohimbine. In the top twenty-five most frequent nitrogen heterocycles in USFDA-approved medications, the indole and imidazole heterocycles are ninth and seventh, respectively. Pyrrole, a five-membered aromatic heterocyclic ring, is a simple and very effective heterocyclic group. Pyrrole derivatives have pharmacological uses as anti-cancer, anti-malarial, anti-diabetic, anti-tuberculosis, anti-viral, anti- bacterial, anti-Parkinson's, and anti-Alzheimer's agents. Several pyrrole- based compounds are already available in pharmaceutical form. For example, calcimycin (A23187) is an antibiotic used to treat Gram-positive bacteria and fungi. Babasin has demonstrated a wide range of biological activities, such as antimalarial, antifungal, and antibiotic properties; however, it is most effective in treating pancreatic cancer. The synthesis of 2,4,5 tri and 1,2,4,5 tetra-substituted imidazole heterocyclic compounds has recently been the subject of intensive research to create powerful anticancer medicines (Figure. 1). The molecular hybridization method uses two or more physiologically active pharmacophores to create new hybrid molecules with potent biological activity. These two important moieties could be combined to form compounds with improved biological activity. Accordingly, the present invention discloses novel anti-cancer compounds; synthesizing said compounds and an anti-cancer pharmaceutical composition comprising said compounds, excipients, adjuvants, fillers, pharmaceutically acceptable salts, etc.

There are various patent and non-patent literature in this field of technology.
Reference of one such patent application no. CN20100128972-A titled as “Application of anthracycline compound in preparing anti-breast cancer medicines” by zhenjian he et al. The prior art discloses an anthracycline compound SZ-685C, with its unique chemical structure represented by formula I, has emerged as a therapeutic agent for breast cancer. This compound has demonstrated anti-tumor activity both in laboratory and animal models. It targets and kills breast cancer cells, including aggressive strains like MCF-7 and MDA-MB-435, while exhibiting minimal toxicity to normal cells. The compound's mechanism of action involves inducing cell death through multiple pathways, making it more potent than traditional treatments.
Another Reference of one such patent application no. IN3921/DEL/2011 titled as “2-Phenyl Benzothlazole linked Imidazole compounds as potential anticancer agents”. The prior art provides 2-phenyl benzothiazole linked imidazole compounds of formula A as anti cancer agent against fifty three human cancer cell lines. (General formula A) wherein (II) R=H or OCH3; R1=H, F or OCH3; R2=H or OCH3; R3=H, NH2, F or OCH3; R4=H, NH2 or OCH3; R5=H, NH2, F, CF3 or OCH3; R6=H or OCH3; R7=H or OCH3; R8=H or OCH3.
Another Reference of one such patent application no. IN202441064567 titled as “Synthesis and biological evaluation of novel Benzo[D]Imidazole bearing Oxadiazolyl-Triazole Derivatives as potential anticancer agents: a computational docking technique. This prior art synthesis of benzo[d]imidazoles connected through an 1,3,4oxadiazole and 1,2,3triazole linkers derivatives 1-12 are synthesized. All the novel compounds (1-12) are characterized by spectral analysis using 1H NMR, 13C NMR spectroscopy and HRMS. The results of the in vitro tests reveal that compounds 6a, 6d, 6h, and 6l exhibit potent anti-proliferative activity against the MDA-MB-415 cell line, with percentage of cell viability ranging from 52.7, 4.8 to 80.1, 2.7% at 1 M of the drug and IC50 values between 26.64 M and 4.93 M. Three benzo[d]imidazole derivatives namely 6b, 6h and 6l showed excellent inhibitory potential against T-47D cell line with IC50 values of 8.03, 0.07, 5.10, 0.23, and 6.78, 0.07 M, respectively in comparison to DXN (IC50 = 4.13, 0.22 M). Especially 6d exhibited potential amino acid stackings ValA:63, LeuA:247, LeuA:35, ArgA:60, AspA:59, AsnA:240, His:64, TyrA:36, and MetA:251 in the active site of estrogen receptor (ER) in breast cancer (PDB: 7UJM) and their docking efficiency 6.29 kcal/mol.
Another Reference of one such patent application no. UAA201305746A titled as “3-(31,51-Ditertbutyl-41-Hydroxyphenyl)-6,7-Dihydro-5H-pyrolyl [1,2-A] Imidazole hydrochloride with anticancer properties”. This prior art relates to organic and pharmaceutical chemistry and medicine, in particular pharmacologically active substances. This compound exhibits antitumor activity and can be used in the melanoma, renal cancer and breast cancer treatment. Investigation of antitumor activity is carried out in vitro on 60 cancer cell lines (leukemia, lung, colon, CNS, melanoma, ovarian, renal, prostate and breast cancer). The claimed compound at a concentration of 10-5 mol/l exhibits the ability to inhibit the growth of cancer cells, covering virtually the entire spectrum of human cancers. It is shown that compound is the most effective towards to melanoma cells SK-MeL-5 (-88,80%), kidney cancer cells RXF-393 (-53,31%) and breast cancer MDA-MB-468 (-21,31 %).
Another reference is made to non-patented document by Naresh Kumar and Nidhi Goel titled as “Recent development of imidazole derivatives as potential anticancer agents”. This paper describes cancer as one of the key health problems globally, is a group of related diseases that share a number of characteristics primarily the uncontrolled growth and invasive to surrounding tissues. Chemotherapy is one of the ways for the treatment of cancer which uses one or more anticancer agents as per chemotherapy regimen. Limitations of most anticancer drugs due to a variety of reasons such as serious side effects, drug resistance, lack of sensitivity and efficacy etc. generate the necessity towards the designing of novel anticancer lead molecules. In this regard, the synthesis of biologically active heterocyclic molecules is an appealing research area. Among heterocyclic compounds, nitrogen containing heterocyclic molecules has fascinated tremendous consideration due to broad range of pharmaceutical activity. Imidazoles, extensively present in natural products as well as synthetic molecules, have two nitrogen atoms, and are five membered heterocyclic rings. Because of their countless physiological and pharmacological characteristics, medicinal chemists are enthused to design and synthesize new imidazole derivatives with improved pharmacodynamic and pharmacokinetic properties. The aim of this present chapter is to discuss the synthesis, chemistry, pharmacological activity, and scope of imidazole-based molecules in anticancer drug development.
Finally, invention discloses the current challenges and future perspectives of imidazole-based derivatives in anticancer drug development.
Another reference is made to non-patented documents by Pankaj Sharma, Chris LaRosa, Janet Antwi, Rajgopal Govindarajan, Karl A. Werbovetz titled as “Imidazoles as potential anticancer agents: An update on recent studies”. The paper describes Nitrogen-containing heterocyclic rings are common structural components of marketed drugs. Among these heterocycles, imidazole/fused imidazole rings are present in a wide range of bioactive compounds. The unique properties of such structures, including high polarity and the ability to participate in hydrogen bonding and coordination chemistry, allow them to interact with a wide range of biomolecules, and imidazole-/fused imidazole-containing compounds are reported to have a broad spectrum of biological activities. This review summarizes recent reports of imidazole/fused imidazole derivatives as anticancer agents appearing in the peer-reviewed literature from 2018 through 2020. Such molecules have been shown to modulate various targets, including microtubules, tyrosine and serine-threonine kinases, histone deacetylases, p53-Murine Double Minute 2 (MDM2) protein, poly (ADP-ribose) polymerase (PARP), G-quadraplexes, and other targets. Imidazole-containing compounds that display anticancer activity by unknown/undefined mechanisms are also described, as well as key features of structure-activity relationships. This review is intended to provide an overview of recent advances in imidazole-based anticancer drug discovery and development, as well as inspire the design and synthesis of new anticancer molecules.
The invention involves the synthesis of new imidazole analogs, which are not mentioned in the prior arts. The specific compounds imidazole-pyridine, imidazole-indole, imidazole-N-methyl pyrrole, and imidazole-quinoline are not covered in the prior art.
The present invention discloses compound 5e, a novel imidazole analog. This compound exhibits superior therapeutic potential by significantly reducing tumor volume while maintaining low toxicity in vivo. This unique combination of efficacy and safety profile is not found in any prior art compounds.

OBJECT OF THE INVENTION:
The main object of the present invention is to provide novel anti-cancer compounds and a method of synthesizing said compounds.

Yet another object of the invention is to provide an anti-cancer pharmaceutical composition comprising said compounds, excipients, adjuvants, fillers, pharmaceutically acceptable salts, etc.

Yet another object of the present invention is to provide an anti-cancer composition comprising imidazole-pyridine, imidazole-pyrrole, and imidazole-indole compounds along with excipients, adjuvants, fillers, pharmaceutically acceptable salts.

Yet another object of the invention is to provide a process of preparing an anti-cancer composition comprising imidazole-pyridine, imidazole- pyrrole, and imidazole-indole compounds along with excipients, adjuvants, fillers, pharmaceutically acceptable salts.

Yet another object of the present invention is to provide an efficacious and improved composition for therapeutic and/or prophylactic action against cancer.

Yet another object of the present invention is to provide an anti-cancer composition that shows synergistic and unexpected effects.

Yet another object of the present invention is to provide a cost-effective composition.

Yet another object of the invention is to provide an anti-cancer composition comprising therapeutic and/or prophylactic actions for breast cancer.

SUMMARY OF THE INVENTION:

Accordingly, the present invention relates to novel anti-cancer compounds and methods of synthesizing said compounds and an anti-cancer pharmaceutical composition comprising said compounds.

The present invention provides a composition and a process thereof comprising of imidazole-pyridine, imidazole-pyrrole, and imidazole-indole scaffolds along with excipients, additives, fillers, pharmaceutically acceptable salts, etc., to provide an efficacious and improved composition for therapeutic and prophylactic action against cancer. The present invention also provides a synergistic composition showing unexpected effects against cancer. The present invention further caters to the needs of the medical sciences by providing a cost-effective composition against cancer. The present invention discloses a novel and rapid process of preparing an anti-cancer composition comprising imidazole-pyridine, imidazole- pyrrole, and imidazole-indole scaffolds along with excipients, additives, fillers, pharmaceutically acceptable salts, etc. to provide an efficacious and improved composition for therapeutic and prophylactic action against the cancer disease. For synthesizing organic compounds and assessing biological activity, the creation of carbon-nitrogen (C-N) and carbon-carbon (C-C) bonds have become crucial priorities in recent years. Introducing a hetero unit at position two of the imidazole scaffold exhibits potential anticancer activity. These results show that imidazole ring modifications at the N-1 and C-2 positions have produced large chemical entities with enhanced anticancer activity. Furthermore, the importance of the phenyl rings at positions 4 and 5 is rising. Purines, essential components of DNA and RNA, form a ring-like shape in imidazole. Imidazole acts on many important biological functions. Some amino acids, particularly histidine, possess an imidazole side chain. Histidine supplementation has improved the cytotoxic effects of numerous chemotherapy drugs on cancer cells in vitro. Histidine is being researched for potential medicinal purposes in addition to its role in human health. Imidazole-based scaffolds have a wide range of therapeutic properties, including antibacterial, antihistaminic, antitubercular, and anticancer activity, which makes them extremely interesting to pharmacological chemists. Lepidiline A and B are naturally occurring imidazolium salts with powerful cytotoxic properties against human cancer cell types. Additionally, possible chemosensitizer molecules that make cancer cells more sensitive to chemotherapeutic agents have been studied concerning imidazole scaffolds. In human cancer cell lines, imidazole and its compounds may enhance the cytotoxic effects of a chemotherapeutic treatment. Analogues of pyrrole found in natural products and co-factors such as vitamin B12, bile pigments such as bilirubin, and porphyrins of hemes, chlorophyll, and chlorins, as well as porphyrinogens. Because of their added activity, pyrrole scaffolds stand out as a scaffold with varied biological properties. When pyrroles are obtained from natural sources, practical problems often occur. According to SAR research, the presence of various substituents, functionalities, and halogens at a specific position of the pyrrole molecule results in extraordinary pharmacophoric capabilities. This suggests that the synthesis of multi-substituted and functionalized NH-pyrroles is advantageous. The synthesis of 2,4,5 tri- and 1,2,4,5 tetra-substituted imidazole heterocyclic compounds has recently been the subject of intensive research to create powerful anticancer medicines as shown in Figure. 1. The molecular hybridization method uses two or more physiologically active pharmacophores to create new hybrid molecules with strong biological activity. These two important moieties could be combined to create compounds with improved biological activity, such as imidazole-pyridine, imidazole-pyrrole, and imidazole-indole- hybrids. Alkyl group and heterocyclic units are attached to the imidazole ring at the first and second locations in this direction. Various experiments have been conducted, and positive results have been obtained showing improvements in cancer patients. Accordingly, the present invention provides a novel anti-cancer compound and method of synthesizing said compounds and an efficacious anti-cancer pharmaceutical composition for patients suffering from cancer.

BRIEF DESCRIPTION OF DRAWINGS
Figure 1 depicts design of tri and tetra-substituted imidazole.
Figure 2 depicts IC50 values of compounds/analogues 5a, 5c, 5d and 5e against four breast cancer cell lines.
Figure 3 depicts IC50 values of compounds 5q, 5r, 5s, 5t and 5u against four breast cancer cell lines.
Figure 4 depicts graphical representation of the effects of 5e and cisplatin on tumor volume (A) and body weight (B).
Figure 5 depicts molecule 5e's interactions with multiple receptors in distinct surface perspectives through amino acids.
Figure 6 depicts molecular docking and amino acid interaction diagrams of 5e with Akt receptor
Figure 7 depicts comparison of HOMO-LUMO energy of the active compounds 5a, 5d, 5e, 5n, 5o, 5q, 5t and 5u.
Figure 8 depicts compounds 5n (c, d) and 5o (a, b) inside the active site of GSK-3ß are shown in 2D (a, c) and 3D (b, d) images (PDB: 5K5N).
Figure 9 depicts compounds 5t, 2D (a) and 3D (b) interactions with the amino acid 7NH5

DETAILED DESCRIPTION OF THE INVENTION
Some embodiments of the present disclosure, illustrating all its features, will now be discussed in detail. It must also be noted that as used herein and in the appended claims, the singular forms "a", "an" and "the" include plural references unless the context clearly dictates otherwise.

Various modifications to the embodiment will be readily apparent to those skilled in the art and the generic principles herein may be applied to other embodiments. However, one of the ordinary skills in art will readily recognize that the present disclosure including the definitions listed here below are not intended to be limited to the embodiments illustrated but is to be accorded with the widest scope consistent with the principles and features described herein.

A person of ordinary skill in art will readily ascertain that the illustrated steps detailed in the figures and here below are set out to explain the exemplary embodiments shown, and it should be anticipated that ongoing technological development will change the way functions are performed. These examples are presented herein for purposes of illustration, and not limitation. Further, the boundaries of the functional building blocks have been arbitrarily defined herein for the convenience of the description. Alternative boundaries defined as the specified functions and relationships thereof are appropriately performed. Alternatives (including equivalents, extensions, variations, deviations, etc., of those described herein) will be apparent to persons skilled in the relevant art(s) based on the teachings contained herein. Such alternatives fall within the scope and spirit of the disclosed embodiments.

Before discussing example, embodiments in more detail, it is to be noted that the drawings are to be regarded as being schematic representations and elements that are not necessarily shown to scale. Rather, the various elements are represented such that their function and general purpose becomes apparent to a person skilled in the art.

Any connection or coupling between functional blocks, devices, components, or other physical or functional units shown in the drawings or described herein may also be implemented by an indirect connection or coupling. A coupling between components may also be established over a wireless connection. Functional blocks may be implemented in hardware, firmware, software, or a combination thereof.

Further, the flowcharts provided herein, describe the operations as sequential processes. Many of the operations may be performed in parallel, concurrently, or simultaneously. In addition, the order of operations re-arranged. The processes may be terminated when their operations are completed but may also have additional steps not included in the figured. It should be noted, that in some alternative implementations, the functions/acts/ steps noted may occur out of the order noted in the figured. For example, two figures shown in succession may, in fact, be executed concurrently, or may sometimes be executed in the reverse order, depending upon the functionality/acts involved.

Further, the terms first, second etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers, and/or sections should not be limited by these terms. These terms are used only to distinguish one element, component, region, layer or section from another region, layer, or a section. Thus, a first element, component, region layer, or section discussed below could be termed a second element, component, region, layer, or section without departing form the scope of the example embodiments.

The terminology used herein is for the purpose of describing example embodiments only and is not intended to be limiting. Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which example embodiments belong. It will be further understood that terms, e.g., those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

As used herein, the singular forms “a,” “an,” and “the,” are intended to include the plural forms as well, unless the context clearly indicates otherwise. As used herein, the terms “and/or” and “at least one of” include all combinations of one or more of the associated listed items. It will be further understood that the terms “comprises,” “comprising,” “includes,” and/or “including,” when used herein, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.
The present invention discloses novel anti-cancer compounds, method of synthesizing said compounds and an anti-cancer pharmaceutical composition comprising said compounds. The present invention relates to imidazole-pyridine, imidazole-pyrrole, and imidazole-indole compounds and synthesizing of said compounds with anti-cancer pharmaceutical composition along with excipients, adjuvants, fillers, pharmaceutically acceptable salts, etc.

SYNTHESIS OF DESIGNED SCAFFOLDS
A one-pot synthesis is carried out as shown in Scheme 1, in which the starting materials namely, diketone, heterocyclic aldehydes, and ammonium acetate are dissolved in ethanol and catalytic quantity of iodine are added. The reaction mixture is heated to 78-85 °C and stirred at the same temperature for 15 to 20 hours. The progress of reaction is monitored through TLC and visualized under UV light; the reaction is stopped once the starting material, aldehyde, is consumed. The reaction mixture is cooled to room temperature and diluted with water (5 V) and extracted using ethyl acetate (10 V); organic layer is dried over Na2SO4, filtered and concentrated to get crude product, which is purified by column chromatography using ethyl acetate and petroleum ether as an eluent, to yield the pure compound of 5a, 5k, 5q, 5v and 5f’.

The 1H and 13C NMR spectra are used to determine the structures of the obtained compounds along with FTIR and MS. The target compounds displayed [M+] ion peaks in the ESI-MS analysis. The FTIR spectra of target compound 5a revealed N-H stretching-induced absorption at 3742 cm-1. The aromatic structure's C-H stretching frequency is observed at 3064 cm-1, C=N at 1695 cm-1 and C=C at 1519 cm-1, respectively. The C-N group also causes a band at 1021 cm-1.

On the other hand, the aromatic protons of compound 5a appeared as a multiplet in the 1H NMR spectrum between 7.12 and 7.42. Pyridine ring hydrogens are visible as a singlet and doublet between 8.40 and 9.05 ppm. The 5a’s 13C NMR data revealed pyridine ring signals at 148.83, 145.84, and 142.75 ppm; aromatic ring signals at 136.91, 133.41, 129.29, 127.80, 126.77, and 123.92 ppm, methyl carbon signal at 21.27 ppm supported the structure. According to the chemical formula C22H19N3, the mass analysis of 5a revealed a molecular ion peak at m/z =325.10 (M+). The compound 5k's FTIR spectrum revealed a band at 3382 cm-1 that matched the N-H spectrum, indicating the imidazole moiety is present. The 1H-NMR spectra of compound 5k showed a sharp singlet of -NH protons at 11.37 and 12.27 ppm, respectively, corresponding to the -NH proton in the indole ring and all other aromatic protons in the range of 7.12 and 7.64. Additionally, the doublet and singlet signals at ppm 8.47-8.48 and 7.99, respectively, stand in for the second and fourth positions of the indole scaffold. The imidazole and indole rings interacted with the second and third-position carbons at 144.19 and 107.28, respectively, in the 13C NMR spectra of compound 5k. The carbon atoms in the imidazole ring, connected to the two phenyl rings, also appeared at 136.43 and 136.73, and the carbon in the indole-C7 position at 112.07. All of the other aromatic carbons appeared between 136.17 and 129.15. The characteristic [M+] corresponding peaks corresponding to their chemical formulae are visible in the mass spectrum 5k. The target compound 5q shows a molecular ion peak, m/z = 300.23 [M+H]+ in LC-MS. FTIR spectra represented the N-H bond at 3581 cm-1, indicating imidazole nitrogen's presence. The 1H NMR shows all the respective protons. The CH3 proton from the pyrrole ring was observed as a singlet at 3.85 ppm. The pyrrole hydrogen peaks are observed at 6.21 ppm, 6.37 ppm, and 6.77 ppm, while the phenyl ring protons are observed between 7.12-7.51 ppm. The 13C NMR spectrum of compound 5q represents all the carbons in the compound, phenyl carbons observed at 127-141 ppm, and the pyrrole carbons observed at 107-123 ppm. The CH3 carbon attached to the pyrrole nitrogen was observed at 36 ppm. The spectroscopic methods indicated above confirm the planned scaffolds' structural integrity.

Scheme 1: Synthesis of 2,4,5-trisubstituted imidazoles.

The inventions of the new molecules also include a four-component reaction, in which diketone, heterocyclic aldehyde, ammonium acetate, and the suitable amine are used. All the starting materials/reagents are dissolved in ethanol, a predetermined amount of iodine is added, and the reaction is heated at 78-85 °C and maintained at same temperature for 16 h as shown in Scheme 2. The reaction is monitored by TLC, and it is visualized under UV light. After completion of the starting material, the reaction is cooled to room temperature, diluted with water (5 V), extracted with ethyl acetate (10 V), organic layer is dried over Na2SO4, filtered and concentrated under reduced pressure to get crude compound, which is purified by silica gel column chromatography using ethyl acetate and petroleum ether as an eluent to afford pure compound of 5c-5e, 5j, 5l-5p, 5r, 5f, 5u, 5d’, 5e’, and 5g’-5j’. All the compounds are characterized using mass, NMR (1H & 13C), and FTIR, with all the spectral data complying with the desired product.

Scheme 2: Synthesis of 1, 2, 4, 5-tetrasubstituted imidazoles.

As some of the aliphatic amines are not available, those desired side-chain substitution is obtained by performing N-alkylation reactions on tri-substituted product. The compounds 5a, 5k, 5q, 5v and 5f’ are alkylated using various alkylating agents using anhydrous K2CO3 as base in acetonitrile medium. The resulting reaction mixture is heated at 85-90 °C and maintained at the same temperature for 16 h. The reaction is monitored by TLC and it is visualized under UV light. After completion of the starting material, the reaction is cooled to room temperature, diluted with water (5 V), extracted with ethyl acetate (10 V), organic layer was dried over Na2SO4, filtered and concentrated under reduced pressure to get crude compound, which is purified by silica gel column chromatography to afford N-alkylated (5b, 5f-5i and 5s) 1, 2, 4,5-tetra substituted imidazole respectively as shown in Scheme 3.

The assigned structures for compounds 5b, 5f–5i, 5s, 5w-5z, and 5a’-5c’ are confirmed by their spectral analysis namely, NMR (1H and 13C NMR), FTIR, and MS spectra.

Scheme 3: N-alkylation Reactions

Biological Evaluation
In vitro
Pyridine has a wide range of biological activities, such as activating enzymes, EGFR, and HER-2 kinase. The imidazole-pyridine hybrids are evaluated against MCF7, BT474, T47D, MDA-MB-468, and a normal cell line L929 (mouse fibroblast cells) and cisplatin is used as the standard drug.

According to Table 1, the molecules 5a-5j are shown to have excellent inhibitory effects against the target cell line. The potencies of compounds 5a, 5c, 5d, and 5e are higher than those of the other compounds as shown in Figure. 2. Especially the more potent cytotoxicity activity of 5e against the BT474 cell line (IC50 = 39.19±1.12 µM at 24 h and 39.85±1.25 µM at 48 h).

However, the BT474 cell line proved highly active against 5c (IC50 = 35.98±1.09 µM at 24 h and 40.47±1.13 µM at 48 h) and 5d (IC50 = 35.56±1.02 µM at 24 h and 39.62±1.09 µM at 48 h), respectively. In comparison to compounds 5c, 5d, and 5e, which have an alkyl substitution at the N1 position of the imidazole ring, compound 5a has a slightly higher IC50 value (IC50 = 45.82±1.32 µM at 24 h and 42.40±1.21 µM at 48 h). Additionally, invention evaluated the cytotoxicity of compounds 5a, 5c, 5d, and 5e against the MDA-MB 468 cell line after 24 and 48 hours. The results showed that compound 5c had strong inhibitory activity (IC50 = 43.46±1.08 µM at 24 h and 49.23±1.21 µM at 48 hours). A decrease in the IC50 value (>100 µM) was seen as the length of the alkyl chain in the imidazole ring on the N1 position increased. The cytotoxicity of the active compounds 5a, 5c, 5d, and 5e are evaluated against the normal cell line L929 (mouse fibroblast cells) to estimate the IC50 and assess their safety. The results are shown in Table 1. All the active compounds exhibited moderate IC50 values against the L929 cell line (88.41±1.08, 48.12±1.17, 57.24±1.05, 67.24±1.12 µM). The outcomes showed that in the BT474 cell line, 5e showed more potent cytotoxic activity.

Table 1. In vitro cytotoxicity of 5a-5j on various breast cancer cell lines at 24 h and 48 h

Code Mouse fibroblast cell line
IC50a ±SD (µM) Breast cancer cell lines
[IC50a ±SD (µM)]
L929 MDA-MB 468 BT 474 T47D MCF7

24h 48h 24h 48h 24h 48h 24h 48h
5a 88.41±1.08 50.08±1.24 49.98±1.13 45.82±1.32 42.40±1.21 >100 µM >100 µM >100 µM >100 µM
5b 26.59±1.32 97.88±1.36 100.21±1.69 97.10±1.21 72.48±1.46 >100 µM >100 µM >100 µM >100 µM
5c 48.12±1.17 43.46±1.08 49.23±1.21 35.98±1.09 40.47±1.13 83.16±1.04 >100 µM 81.66±2.13 >100 µM
5d 57.24±1.05 43.48±1.19 82.75±1.5 35.56±1.02 39.62±1.09 44.11±1.16 >100 µM 48.15±1.19 >100 µM
5e 67.24±1.12 50.08±1.07 82.39±1.69 39.19±1.12 39.85±1.25 48.8±1.72 97.24±2.34 92.11±2.14 >100 µM
5f 198.8±1.85 >100 µM 94.47±2.36 >100 µM 92.97±1.95 >100 µM 90.61±3.2 >100 µM >100 µM
5g 283.79±2.13 >100 µM >100 µM >100 µM >100 µM >100 µM >100 µM >100 µM >100 µM
5h 346.62±1.51 >100 µM >100 µM >100 µM >100 µM >100 µM >100 µM >100 µM >100 µM
5i 409.37±1.39 >100 µM >100 µM >100 µM >100 µM >100 µM >100 µM >100 µM >100 µM
5j 87.61±1.62 >100 µM >100 µM >100 µM >100 µM >100 µM >100 µM >100 µM >100 µM

The cell viability of normal cells Vero, 3T3-L1, H9c2, L929, TH-1B1, MCF7, A-431, A549, Caco-2, SKOV-3, HeLa, HepG2, SK-MEL-2, B16F10, SKNSH, SH-SY5Y was estimated to use MTT assay at different concentrations for synthesized compounds (5k-5p). The IC50 results are shown in Table 2. Compounds 5n and 5o displayed good cytotoxic activity in most tested cell lines, significantly higher than standard drugs. The HeLa cervical epithelioid cancer cell line was more responsive to 5n (4.26±1.21 µM) than to 5o (10.84± 1.17 µM) indicating moderate activity. IC50 values for compounds 5n and 5o against all tested cancer cell lines, ranged from 10.06±1.69 to 37.43±1.23 µM, except for MCF7. These compounds are found to display cytotoxic activity. In the case of the MCF7 breast cancer cell line, the activity of 5n and 5o is decreased, with IC50 values of 93.25±1.4 and 118.54±1.08 µM, respectively. The cytotoxicity of the synthetic compound 5o was reported to be substantially less than that of sorafenib (IC50 value = 9.18±0.6 µM), with an IC50 value of 7.87±1.01 against HepG-2 cells. The imidazole-indole conjugates, 5n and 5m with alkyl substitutions at the N1-position of the imidazole exhibited high activity in the synthesized compounds against the SK-OV-3 cell line with IC50 values of 10.99±1.32 µM and 11.41±2.51 µM, respectively, as well as compound 5e with IC50 values of 16.45±1.21 µM, 17.44 ±1.13 µM and 20.31±1.69 µM. The cytotoxicity of the most active compounds, 5n and 5o, against the healthy cell lines Vero, 3T3-L1, H9c2, and L929 are evaluated. According to the results, the synthesized imidazole-indole scaffolds are possible molecules for upcoming research and development of anticancer drugs.

Table 2: Cytotoxicity of compounds 5k-5p against a selection of cancerous and normal cell lines
In-vitro Cytotoxicity (IC50 (µM) ±SD
Cell line 5k 5l 5m 5n 5o 5p
VERO 62.67±1.08 111.33±1.32 55.85±1.17 100.29±1.05 111.33±1.12 60.37±1.85
3T3L1 49.04±2.13 44.97±1.51 36.31±1.25 112.30±1.13 122.39±1.36 49.59±1.62
H9C2 21.4±1.21 24.49±1.39 65.25±2.1 108.14±1.01 109.18±1.17 40.59±1.59
L929 26.13±1.06 49.23±1.12 34.29±2.69 85.16±1.05 91.25±1.21 61.7±1.52
TH1B1 133.1±1.47 23.33±2.35 122.3±1.95 49.78±1.18 89.03±1.09 83.14±1.78
MCF7 48.85±1.24 49.95±1.36 91.01±2.2 93.25±1.4 118.54±1.08 120.36±2.3
A549 52.53±2.71 50.69±1.90 49.95±2.6 12.5±1.19 37.43±1.23 78.89±1.67
Caco-2 4.96±1.98 3.95±1.21 5.82±1.88 10.06±1.69 14.94±1.12 36.34±2.10
SK-OV-3 20.31±1.69 17.44±1.13 11.41±2.51 10.99±1.32 16.45±1.21 28.44±1.59
A431 14.93±2.30 43.32±1.86 26.85±1.74 21.01±1.69 10.47±1.21 36.11±1.12
HeLa 12.12±2.12 19.71±1.50 6.09±2.10 4.26±1.21 10.84±1.17 55.08±1.13
HePG2 80.96±1.37 83.32±1.69 53.46±1.04 13.64±1.16 7.87±1.01 26.36±1.39
SKMel2 8.94±1.21 74.51±1.68 35.75±1.09 31.85±1.58 22.95±1.33 85.62±1.72
B16F10 24.3±1.19 41.38±1.25 32.01±1.98 33.32±1.29 12.97±1.14 31.67±2.31
SKNSH 26.48±1.96 39.65±2.35 37.16±1.47 34.93±1.32 9.60±1.09 23.02±1.87
SHSY5Y 32.21±2.01 19.65±1.32 42.88±1.25 16.6±1.17 28.1±1.10 29.50±1.49

In the present invention, the imidazole ring's second position is linked to another heterocyclic unit. The stability is due to the aromatic nature of the pyrrole, it interacts by p-p stacking with protein or DNA. Pyrrole is a crucial biological active unit in the process of developing anti-cancer drugs. Additionally, the structure-activity relationship (SAR) helps in improving these compounds' therapeutic properties. These properties are essential in developing drugs that target the DNA of cancer cells. The cytotoxic activity of the molecules (5q-5u) was tested against MDA-MB-468, BT474, T47D, MCF7, and a normal cell line L929 (mouse fibroblast cells). As shown in Table 3, the molecules 5t and 5u exhibited potent inhibitory activity against the targeted breast cancer cell lines. The inhibitory activity of the compounds 5t and 5u are higher than those of the other compounds as shown in Figure 3. The more potent cytotoxic activity of 5t and 5u against the BT474 cell line (IC50 = 25.69±1.09 µM and 32.08±1.45 µM at 24 h), MDA-MB 468 and 5t (IC50 = 43.46±1.52 µM at 24 h) and 5u (IC50 = 47.30±1.20 µM at 24 h), proved to be active against T47D cell line. Compared to compounds 5q, 5r, and 5s, which contain a short alkyl substitution on the imidazole nitrogen, compound 5q has a higher IC50 value (IC50 = 100 µM at 24 h). Additionally, invention evaluated the cytotoxicity of compounds 5q-5u against the MCF7 cell line after 24 h. The results showed that compound 5t had potent inhibitory activity (IC50 = 45.39±2.34 µM at 24 h). The cytotoxicity of the active compounds 5q-5u was then evaluated against the normal cell line L929 (mouse fibroblast cells). The results are shown in Table 3. All the molecules are moderately active against the L929 cell line (8.59±1.69, 6.35±1.22, 36.4±1.01, 32.29±1.05 and 30.50±1.31 µM). The outcomes showed that in the BT474 cell line, 5t and 5u showed a more potent cytotoxic activity.

Table 3. In vitro cytotoxicity of 5q-5u on various breast cancer cell lines at 24 h
Code Mouse fibroblast cell line
IC50 ±SD (µM) Breast cancer cell lines
[IC50 ±SD (µM) after 24 h]
L929 MDA-MB 468 BT 474 T47D MCF7
5q 8.59±1.69 >100 µM 96.18±1.46 >100 µM >100 µM
5r 6.35±1.22 55.20±2.31 72.60±1.69 >100 µM >100 µM
5s 36.4±1.01 74.18±1.69 68.58±1.25 >100 µM >100 µM
5t 32.29±1.05 43.46±1.52 25.69±1.09 38.57±1.25 45.39±2.34
5u 30.50±1.31 47.30±1.20 32.08±1.45 47.63±1.62 82.56±1.63

In vivo anti-tumor efficacy of 5e
The effectiveness of compound 5e as a treatment is assessed using a mouse model containing Ehrlich Ascites Carcinoma (EAC) cells. The test compound 5e and the positive control, 2.5 mg/kg of cisplatin, are given every day for 26 days. The positive control cisplatin was given at a dose of 2.5 mg/kg intraperitoneally, which was known at doses of 50 mg/kg and 250 mg/kg. The findings demonstrated that cisplatin and 5e inhibited tumor growth in this mouse model. Beginning on day 6 of the medication treatment, a considerable decrease in tumor volume was observed. After the treatment of 50 mg/kg and 250 mg/kg, the tumor size was reduced by approximately 50% and 66% after the trial (i.e., day 26) as shown in Figure. 4.

The HOMO and LUMO orbitals are localized throughout the entire molecule, as shown in Figure. 7, according to the imidazole-pyridine, imidazole-indole, and imidazole-pyrrole scaffolds 5a, 5d, 5e, 5n, 5o, 5q, 5t and 5u. In compound 5n, the HOMO-LUMO orbitals have energies of EHOMO = -0.15 Ha and ELUMO = -0.07 Ha, respectively. The compound 5o, with EHOMO = -0.17 Ha and ELUMO = -0.04 Ha, it was shown that the HOMO orbital was compressed over the indole scaffold group. The lowest energy band gaps for both compounds, 5n and 5o, are E = 0.08 Ha and E = 0.13 Ha, respectively. Notably, the lowest total energy was found in the two compounds with the highest activity, 5n and 5o. Compared to 5o (ETotal value of -1353.01 Ha), the compound 5n has an ETotal of -1314.07 Ha. Given that compounds 5n and 5o are less stable and more reactive, these results may demonstrate the potency of biological activity as shown in Table 4.

The selected compounds (5a-5p) are dock into the GSK-3ß crystal structure's ligand binding pocket (PDB ID: 5K5N). The lead compounds 5n and 5o received scores of -13.06 and -13.59, respectively, while the natural ligand 6QH and the proposed compound had scores of -8.13. According to our docking tests, most of the intended target substances have potential affinities to connect with GSK3ß. Additionally, the binding affinity of the compounds 5d and 5e was estimated (Figure. 8). The compounds (5q-5u) dock with 4KZN, 7NH5, 5W9C, 3QYC, and 5GPG proteins. 7NH5 had one of the best docking scores of all the receptors. Therefore, molecular docking was used to predict the binding affinities of the most potent synthetic compounds, 5t and 5u, and compared with 5q, the series' core molecule. Even though the basic molecule 5q demonstrated a greater binding affinity (-10.3) than the lead compounds 5t and 5u, experimentally, the 5q molecule was not active towards the selected breast cancer cell lines. As a result, the lead compounds 5t and 5u obtained scores of -9.5 and -9.7 Kcal/mol, respectively. The stable 2D and 3D structures of the most active molecule, 5t, is shown in Figure 9.

Table 4: DFT calculation for activity molecules
Compound Total Energy (Ha) Binding Energy (Kcal/mol) HOMO Energy (Ha) LUMO Energy (Ha) Dipole Mag
(A m2)
5a -1004.81 -9.211 -0.18 -0.06 1.13
5d -1277.38 -12.88 -0.17 -0.06 1.39
5e -1316.31 -13.39 -0.18 -0.06 1.06
5n -1314.07 -13.06 -0.15 -0.07 3.54
5o -1353.01 -13.59 -0.17 -0.04 1.78
5q - 936.48 - 10.3 - 0.18 - 0.04 0.55
5t - 1211.60 - 9.5 - 0.20 - 0.03 1.48
5u - 1250.90 - 9.7 - 0.18 - 0.03 1.12

Drug-likeness and ADME prediction
In silico predictions of the drug-likeness, physicochemical characteristics, or ADME attributes have increased the likelihood of identifying novel lead compounds in less time than conventional methods. In silico research is carried out to verify the validity of the results from in vitro biological experiments. The drug-likeness of the compounds is evaluated using several parameters, including the Veber Rule, Lipinski's Rule of Five, and oral bioavailability. Molecular weight, lipophilicity, hydrogen bond donors, and hydrogen bond acceptors are all evaluated using Lipinski's rule of five. The Veber Rule evaluates the number of rotatable bonds in a molecule. These principles are used to determine whether a substance is likely to have positive pharmacokinetic qualities. The oral bioavailability of the proposed medications was considered in addition to these regulations. These computational results consider the characteristics such as solubility, stability, permeability, and metabolic clearance, all of which are required for oral medication to be well absorbed and enter the systemic circulation. By utilizing this assessment, the degree of drug-likeness of the compounds was ascertained, providing insight into their potential as future therapeutic development options. Over the past few decades, physical-chemical and pharmacokinetic features have emerged as one of the most important stages in the development of novel medications. All active substances follow the Veber rule and Lipinski's Rule of Five (5a, 5d, 5e, 5n, 5o, 5t, and 5u). Five compounds, 5e, 5f, 5g, 5h, 5i, 5j, 5p, 5a’, 5b’, 5c’ and 5k’, violated the Veber rule by having more than ten rotatable bonds and 5h, 5i, 5j, 5p and 5b’ violated the Lipinski rule of five by having molecular weights larger than 500 Da. They also scored poor on the drug-likeness scale. For all compounds, physicochemical and pharmacokinetic parameters are provided in Table 5.
Table 5: In silico analysis of the physicochemical and pharmacokinetic properties of imidazole hybrids (5a-5z and 5a’-5k’)
Code Lipinski’s Rule Veber Rule Pharmacokinetics Drug likeness
MW < 500 MLogP = 4.15 nHBA = 10 nHBD = 5 nRB = 10 TPSA = 140 Å2 GI BBB LogKp
-5.26 cm/s Bioavailability score
5a 325.41 3.29 2 1 3 41.57 high yes -4.94 0.55
5b 367.49 3.92 2 0 5 30.71 high no -4.64 0.55
5c 381.15 4.13 2 0 6 30.71 low no -4.48 0.55
5d 423.59 4.72 2 0 8 30.71 low no -3.68 0.55
5e 437.62 4.91 2 0 10 30.71 low no -3.28 0.55
5f 465.67 5.29 2 0 12 30.71 low no -2.69 0.55
5g 493.73 5.66 2 0 14 30.71 low no -2.08 0.55
5h 521.78 6.02 2 0 16 30.71 low no -1.49 0.17
5i 549.83 6.37 2 0 18 30.71 low no -0.89 0.17
5j 575.87 6.65 2 0 19 30.71 low no -0.94 0.17
5k 335.40 3.63 1 2 3 44.47 high yes -4.68 0.55
5l 349.43 3.84 1 1 3 33.61 high yes -4.79 0.55
5m 391.51 4.45 1 1 6 33.61 low no -4.21 0.55
5n 433.59 5.04 1 1 8m 33.61 low no -3.01 0.55
5o 447.61 5.23 1 1 10 33.61 low no -4.55 0.55
5p 585.86 6.95 1 1 19 33.61 low no -0.67 0.17
5q 299.37 2.88 1 1 3 33.61 high yes -5.41 0.55
5r 355.48 3.75 1 0 6 22.75 high no -4.95 0.55
5s 369.50 3.96 1 0 7 22.75 low no -4.65 0.55
5t 397.56 4.36 1 0 8 22.75 low no -4.15 0.55
5u 411.58 4.56 1 0 10 22.75 low no -3.75 0.55
5v 335.35 3.64 3 1 3 33.61 high yes -5.49 0.55
5w 363.40 4.07 3 0 4 22.75 high no -5.48 0.55
5x 391.46 4.49 3 0 6 22.75 low no -5.02 0.55
5y 419.51 4.90 3 0 8 22.75 low no -4.43 0.55
5z 447.56 5.29 3 0 10 22.75 Low no -3.83 0.55
5a’ 475.62 5.68 3 0 12 22.75 low no -3.23 0.55
5b’ 503.67 6.05 3 0 14 22.75 low no -2.63 0.17
5c’ 531.72 6.41 3 0 16 22.75 low no -2.03 0.17
5d’ 433.34 5.10 3 0 8 22.75 low no -4.22 0.55
5e’ 429.44 5.32 4 0 4 22.75 low no -4.85 0.55
5f’ 347.41 3.54 2 1 3 41.57 high no -4.68 0.55
5g’ 375.47 3.95 2 0 4 30.71 high no -4.68 0.55
5h’ 403.52 4.35 2 0 6 30.71 low no -4.22 0.55
5i’ 445.60 4.93 2 0 8 30.71 low no -3.42 0.55
5k’ 487.68 5.49 2 0 12 30.71 low no -2.42 0.55

Apart from all the molecules which invention have synthesized and taken for in vitro and in vivo studies; present invention has also synthesized more molecules with imidazole-quinoline and imidazole-pyrrole in which 4th and 5th position substituted with p-flurophenyl rings to enhance the bioactivity.

Conclusions
The present invention discloses the synthesis of substituted imidazole-pyridine, substituted imidazole-indole, substituted imidazole-pyrrole, and substituted imidazole-quinoline scaffolds. One-pot and N-alkylation reactions are employed to produce a total of 36 compounds. Ten molecules in the imidazole-pyridine scaffold, six in the imidazole-indole scaffold, and fifteen in the imidazole-pyrrole scaffolds are synthesized, evaluated for their in vitro and in silico properties, and the behavior of the active molecule is examined in vivo. The synthesized compounds are then examined for their cytotoxicity against several normal and cancer cell lines, including Vero, 3T3-L1, H9c2, L929, TH-1B1, MCF7, A549, Caco-2, SKOV-3, A-431, HeLa, HepG2, SK-MEL-2, B16F10, SKNSH, SH-SY5Y, MDA-MB-468, BT-474, T-47D and MCF7.
It is evident that altering the N1 position of the imidazole with various alkyl chain boosted its cytotoxic action. These findings suggest innovative imidazole ring systems coupled to alkyl chains (up to C8) may be advantageous. At 24 hours, compounds 5e and 5t showed cytotoxic action (IC50 = 39.19±1.12 and 25.69±1.09 µM) toward BT474 cell line. From in silico toxicity prediction experiments it showed that compound 5e is not naturally mutagenic or carcinogenic. In the in vivo anti-breast cancer experiment, the 5e molecule demonstrated an impressive reduction of tumor volume (50 to 66%). According to research on molecular modeling, compound 5e displayed high binding energy. According to the ADME study, compounds 5e and 5t complies with Lipinski's rule of five and have an adaptable pharmacokinetic profile. The findings suggested that compounds 5e and 5t might be used to treat breast cancer. A new series of indole-imidazole moiety combinations was created, and their cytotoxic potential against diverse cell types was assessed. The anticancer properties of all identified hybrids are examined, and the hybrids 5n and 5o found to be more effective against different cell lines, with an IC50 value ranging from 4.2 to 37.43 µM. Compared to the other compounds in the series, it was discovered that molecule 5o, which contains a short alkyl chain unit, is the most active of all the compounds. At doses up to 100 µM, all of the assessed chemicals are non-toxic to healthy cells. The compounds prevented breast cancer cell line's cell proliferation. The compounds significantly and profoundly inhibited the development of human cancer. The active compound cytotoxicity data and modeling studies could be seen as prototypes for upcoming research and development.
Examples:
Experimental Data
General procedure for the synthesis of 5a, 5k, 5q, 5v and 5f’
Diketone (10 mmol, 1 equiv.), heterocyclic aldehyde (10 mmol, 1 equiv.), and ammonium acetate (30 mmol, 3 equiv.) are mixed with 10 mL of ethanol and then added the predetermined amount of catalyst iodine, reaction mixture was heated at 78-85 °C for 8 to 15 hours. TLC is employed to track the progress of the reaction, when the starting material is found consumed, the ethanol solvent is removed under vacuum in a rotary evaporator. The obtained residue is diluted with water and extracted with ethyl acetate, the organic layer is washed with brine and dried over anhydrous Na2SO4. The crude product is purified using column chromatography on silica gel (particle size: 60–120 mesh) with petroleum ether/ethyl acetate as an eluent to yield the products 5a, 5k, 5q, 5v and 5f’ as shown in Table 6.

Table 6. Structure, characterization and details of compounds 5a, 5k, 5q, 5v and 5f’
Compound Compound code Analytical data Yield, Appearance, mp, Rf

5a 1H NMR (400MHz, CDCl3) d (ppm): 2.35 (s, 6H), 7.12-7.42 (m, 9H), 8.29-8.32 (t, 1H), 8.40-8.42 (d, 1H), 9.05 (d, 1H), 9.05 (d, 1H), 11.00 (s, 1H). 13C NMR (100MHz, CDCl3) d: 21.2, 123.9, 126.7, 127.8, 129.2, 133.4, 136.9, 142.7, 145.8, 148.8. FTIR (cm-1): 3568 (N-H), 3064 (Ar-H), 2924 (-CH str in CH3), 1519 (C=N), 1456 (C=C), 1021 (C-N), 816, 769 (Ar-H). MS (ESI +ve): 325.10 (M+). 72%, Yellow solid, 171-172 °C, 0.24 (50% E/P)

5k 1H NMR (400MHz, DMSO-d6) d (ppm): 7.12 – 7.23 (m, 3H), 7.31 – 7.38 (m, 3H), 7.45 – 7.53 (m, 6H), 7.63-7.64 (d, 2H), 7.99 (s, 1H), 8.47-8.48 (d, 1H), 11.37 (s, 1H), 12.27 (s, 1H). 13C NMR (101MHz, DMSO) d (ppm): 107.2, 112.0, 120.1, 121.9, 122.3, 124.2, 125.5, 126.6, 127.3, 127.8, 128.6, 129.1, 136.4, 136.7, 144.1. FTIR (? cm-1): 3382 (Imidazole N-H), 3099 (Indole N-H), 2998 (aromatic C-H), 1643 (C=C), 1244 (C-N).MS (ESI +ve): 335.15 (M+). 78%, White solid 156-157 °C, 0.21 (30% E/P)

5q 1H NMR (400 MHz, CDCl3) d (ppm): 0.65 (t, 3H), 1.00 - 1.05 (m, 2H), 1.32 - 1.35 (m, 2H), 3.85 (s, 3H), 3.88 (t, 2H), 6.21 (t, 1H), 6.37(d, 1H), 6.77 (t, 1H), 7.12 - 7.20 (m, 3H), 7.40 - 7.42 (m, 5H), 7.51 (d, 2H); 13C NMR (100 MHz, CDCl3) d (ppm): 36.4, 107.9, 108.2, 123.5, 125.5, 127.5, 127.6, 127.8 127.9, 128.7, 141.1, 141.4, 143.1, 145.2; FTIR (? cm-1): 3581 (Imidazole N-H), 1261 (C-N), 695 (Ar-H); LC-MS (ESI +ve): 300.23 [M+H]+. 70%, White solid, 169-176 °C, 0.18 (10% E/P).

5v 1H NMR (400 MHz, CDCl3) d (ppm): 4.02 (s, 3H), 6.07 (t, 1H), 6.67 (dd, 1H), 6.87 (s, 1H), 7.14 (t, 2H), 7.29 (t, 2H), 7.55-7.48 (m, 4H), 12.33 (s, 1H); 13C NMR (100 MHz, CDCl3) d (ppm): 36.2, 107.8, 108.32, 115.5, 115.7, 123.1, 125.4, 129.3, 129.4, 140.9, 160.9, 163.4.; FTIR (cm-1): 3157 (C-H in aromatic), 1496 (C-C in aromatic), 1224 (C-N in aromatic amine), 831, 706 (C-H in alkenes); LC-MS = m/z = 335.12, observed 336.25 [M+H]+, LC purity 94.26. 66%, Greenish blue solid, 184-186 °C, 0.17 (10% E/P).

5f’ LC-MS = m/z = 347.41, observed 348.39 [M+H]+, LC purity 95.31 %. 70%, Brown gummy, liquid, 0.15 (10% E/P).

General procedure for the synthesis of 5c-5e, 5j, 5l-5p, 5d’, 5e’ and 5g’-5j’
In ethanol (10 mL), a combination of diketone (10 mmol), heterocyclic aldehyde (10 mmol), an amine (10 mmol), and ammonium acetate (30 mmol) is dissolved, an iodine catalyst is added in the calculated amount and reaction is heated at 78-85 °C. Reaction was monitored by TLC, after the completion of reaction, reaction mixture is diluted with water and extracted with ethyl acetate. The organic layer is then dried over anhydrous Na2SO4, filtered and solvent is removed under vacuum to get crude product which is purified using column chromatography on silica gel (60-120 mesh size) with ethyl acetate/petroleum ether as an eluent to obtain the pure 1,2,4,5-tetrasubstituted imidazoles as shown in Table 7 below.

Table 7. Structure, characterization and other details of compounds 5c-5e, 5j, 5l-5p, 5d’, 5e’ and 5g’-5j’
StrStructure Compound code Analytical data Yield, Appearance, mp, Rf

5c 1H NMR (400MHz, CDCl3) d (ppm): 0.61- 0.65 (t, 3H), 0.95-1.04 (m, 2H), 1.31-1.38 (m, 2H), 2.28 (s, 3H), 2.44 (s, 3H), 3.86-3.90 (t, 2H), 7.01-7.03 (d, 2H), 7.28 (s, 4H), 7.39-7.45 (m, 3H), 8.05-8.08 (t, 1H), 8.66-8.68 (d, 1H), 8.94 (d, 1H). 13C NMR (101MHz, CDCl3) d: 13.2, 19.4, 21.1, 21.4, 32.7, 44.6, 123.5, 126.6, 127.9, 128.1, 128.8, 129.8, 130.0, 130.8, 131.4, 135.9, 136.7, 138.3, 138.6, 144.0, 149.4, 149.5. FTIR (cm-1): 2922 (-CH str in CH3), 2856 (CH aliph.), 1592 (C=N), 1436 (C=C), 1026 (C-N), 806, 671 (Ar-H). MS (ESI +ve): 381.20 (M+). 63%, Yellow solid, 72-73 °C, 0.38 (50% E/P).

5d 1H NMR (400MHz, CDCl3) d (ppm): 0.77-0.80 (t, 3H), 1.01-1.03 (t, 4H), 1.12-1.17 (m, 2H), 1.32-1.34 (d, 4H), 1.47-1.53 (m, 1H), 2.25 (s, 3H), 2.45 (s, 3H), 4.13-4.20 (m, 1H), 6.97-6.99 (d, 2H), 7.27-7.33 (m, 5H), 7.41-7.43 (m, 1H), 7.94-7.96 (t, 1H), 8.68-8.69 (d, 1H), 8.84 (d, 1H). 13C NMR (101MHz, CDCl3) d: 13.9, 21.1, 21.4, 22.4, 26.0, 29.7, 31.2, 36.1, 53.9, 64.3, 123.2, 126.5, 128.7, 128.9, 129.5, 131.5, 131.8, 135.8, 137.6, 138.8, 149.7, 150.4. FTIR (cm-1): 2917 (-CH str in CH3), 2849 (CH aliph.), 1542 (C=N), 1432 (C=C), 1091 (C-N), 808, 605 (Ar-H). MS (ESI +ve): 423.20 (M+). 68%, Brown thick oil. 0.25 (50% E/P)
5e 1H NMR (400MHz, CDCl3) d (ppm): 0.85-.86 (t, 3H), 0.96-0.97 (d, 2H), 1.25-1.29 (m, 6H), 1.63 (s, 15H), 2.28 (s, 1H), 2.45 (s, 1H), 3.85-3.89 (t, 1H), 7.01-7.03 (d, 1H), 7.28 (s, 1H), 7.39-7.46 (m, 2H), 8.06-8.07 (d, 1H), 8.67-8.68 (d,1H), 8.93-8.94 (d, 1H). 13C NMR (101MHz, CDCl3) d: 14.0, 21.1, 21.4, 22.5, 26.1, 28.5, 28.7, 30.5, 31.6, 44.8, 123.5, 126.6, 127.8, 128.0, 128.8, 129.0, 129.8, 130.0, 130.8, 131.4, 136.0, 136.7, 138.6, 144.0, 149.4, 149.5. FTIR (cm-1): 3027 (Ar-H), 2922 (-CH str in CH3), 2857 (CH aliph.), 1567 (C=N), 1458 (C=C), 1023 (C-N), 819, 711 (Ar-H). MS (ESI +ve): 437.25 (M+). LCMS: 438.57 [M+H]+. Retention time: 2.50 min, LC purity 99.81%. 61%, Brown thick oil. 0.25 (50% E/P)
5j 1H NMR (400MHz, CDCl3) d (ppm): 0.88-0.89 (d, 4H), 0.98 (s, 5H), 1.16 (s, 23H), 1.98-2.02 (m, 4H), 2.29 (s, 3H), 2.45 (s, 3H), 3.87-3.91 (t, 2H), 5.3-5.37 (q, 2H), 7.03-7.05 (d, 2H), 7.30 (s, 4H), 7.43-7.45 (d, 3H), 8.07-8.09 (d, 1H), 8.68 (d, 1H), 8.97 (s, 1H). 13C NMR (101 MHz, CDCl3) 12.8, 14.1, 21.1, 21.4, 22.7, 26.1, 27.1, 27.2, 28.5, 29.0, 29.3, 29.5, 29.6, 29.7, 29.7, 30.5, 31.9, 44.7, 123.5, 126.6, 127.9, 128.1, 128.8, 129.6, 129.8, 129.9, 130.3, 130.8, 131.5, 135.9, 136.3, 138.3, 138.6, 144.0, 149.4, 149.5. FTIR (cm-1): 2969 (-CH str in CH3), 2926, 2884 (CH aliph.), 1603 (C=N), 1412 (C=C), 1119 (C-N), 816, 644 (Ar-H). MS (ESI +ve): 575.15 (M+). 70%, Brown thick oil, 0.27 (50% E/P)

5l 1H NMR (400MHz, DMSO) d (ppm): 3.54 (s,1H), 7.13-7.24 (m, 4H), 7.33-7.37 (d, 4H), 7.44 -7.46 (d, 4H), 7.51-7.53 (d, 3H), 7.63-7.64 (d, 2H), 8.00 (s, 1H), 8.47-8.49 (d, 1H)11.37 (s,1H). 13C NMR (101MHz, DMSO) d (ppm): 27.6, 112.8, 118.6, 121.2, 122.6, 123.9, 124.5, 137.5, 138.9. FTIR (? cm-1): 3067 (Indole N-H), 2958 (aromatic C-H), 1607 (C=C), 1268(C-N). MS (ESI +ve): 349.42 (M+). 62%, Pale orange solid, 153-154 °C, 0.16 (30% E/P)

5m 1H NMR (400MHz, DMSO) d (ppm): 0.72-0.75 (t, 3H), 0.95-0.96 (d, 4H), 1.07-1.12 (q, 2H), 1.22-1.27 (d, 9H), 1.40-1.42 (d, 2H), 1.96 (s, 1H), 4.24-4.30 (m, 1H), 7.10-7.18 (m, 5H), 7.30-7.32 (d, 1H),7.44-7.47 (d, 7H), 7.68-7.70 (d, 1H), 9.73 (s, 1H). 13C NMR (101MHz, DMSO) d (ppm): 13.9, 22.2, 22.4, 26.1, 29.7, 31.2, 36.0, 53.9, 116.6, 119.8, 120.3, 122.3, 126.1, 126.2, 126.8, 127.6, 127.9, 128.6, 128.8, 132.1, 132.3, 134.3, 135.8. FTIR (? cm-1): 3031 (Indole N-H), 2923 (aromatic C-H), 1666 (C=C), 1261(C-N) MS (ESI +ve): 433.18 (M+). 59%, Brown solid, 151-152 °C, 0.30 (30% E/P)
5n 1H NMR (400MHz, DMSO) d (ppm): 0.72-0.75 (t, 3H), 0.95-0.96 (d, 4H), 1.07-1.12 (q, 2H), 1.22-1.27 (d, 9H), 1.40-1.42 (d, 2H), 1.96 (s, 1H), 4.24-4.30 (m, 1H), 7.10-7.18 (m, 5H), 7.30-7.32 (d, 1H),7.44-7.47 (d, 7H), 7.68-7.70 (d, 1H), 9.73 (s, 1H). 13C NMR (101MHz, DMSO) d (ppm): 13.9, 22.2, 22.4, 26.1, 29.7, 31.2, 36.0, 53.9, 116.6, 119.8, 120.3, 122.3, 126.1, 126.2, 126.8, 127.6, 127.9, 128.6, 128.8, 132.1, 132.3, 134.3, 135.8. FTIR (? cm-1): 3031 (Indole N-H), 2923 (aromatic C-H), 1666 (C=C), 1261(C-N) MS (ESI +ve): 433.18 (M+). 58%, Brown solid, 148-149 °C, 0.30 (30% E/P)
5o 1H NMR (400MHz, DMSO) d (ppm): 0.77-0.80 (t, 3H), 0.93-1.04 (m, 8H), 1.11-1.18 (m, 2H), 1.34-1.41 (m, 2H), 3.94-3.96 (t, 2H), 7.10-7.24 (m, 5H), 7.47-7.50 (m, 5H), 7.52-7.58 (d, 5H), 7.76 (d, 1H), 8.21 (d, 1H), 11.51(d, 1H). 13C NMR (101MHz, DMSO) d (ppm): 14.3, 22.4, 25.9, 28.3, 28.6, 29.7, 31.4, 44.2, 106.2, 112.0, 120.2, 121.5, 122.4, 124.7, 126.2, 126.3, 126.9, 128.5, 129.0, 129.1, 129.5, 131.4, 131.9, 135.6, 136.3, 136.5, 143.2. FTIR (? cm-1): 3057 (Indole N-H), 2919 (aromatic C-H), 1698 (C=C), 1234(C-N). MS (ESI +ve): 447.12 (M+). 59%, Brown solid, 145-146 °C, 0.24 (30% E/P)
5p 1H NMR (400MHz, DMSO) d (ppm): 0.80-0.84 (t, 3H), 1.14-1.27 (m, 18H), 1.35-1.39 (m, 2H), 1.87-1.97 (m, 3H), 3.93-3.97 (t, 2H), 5.24-5.35 (m, 2H), 7.10-7.23 (m, 5H), 7.46-7.56 (m, 9H), 7.75 (d, 1H), 8.21-8.23 (d, 1H), 11.51 (s, 1H). 13C NMR (101MHz, DMSO) d (ppm): 14.3, 22.5, 25.9, 27.0, 28.4, 28.8, 29.0, 29.1, 29.1, 29.2, 29.4, 29.5, 29.7, 31.7, 3.7, 44.2, 106.2, 112.0, 120.1, 121.5, 122.3, 124.7, 126.2, 126.3, 127.0, 128.4, 128.9, 129.0, 129.5, 130.0, 131.4, 132.0, 135.6, 136.3, 136.5, 143.22. FTIR (? cm-1): 3067 (Indole N-H), 2917 (aromatic C-H), 1698 (C=C), 1236 (C-N). MS (ESI +ve): 586.75 (M+). 60%, Brown solid, 145-146 °C, 0.40 (30% E/P).

5r 1H NMR (400 MHz, CDCl3) d (ppm): 4.10 (s, 3H), 6.17 - 6.18 (m, 1H), 6.44 (d, 1H), 6.74 (t, 1H), 7.29 (d, 2H), 7.34 (t, 5H), 7.57 (br s, 3H); 13C NMR (100 MHz, CDCl3) d (ppm):13.6, 19.2, 32.5, 35.3, 44.3, 110.7, 124.3, 125.9, 126.7, 127.7, 128.6, 128.8, 131.0; FTIR (? cm-1): 1593 (aromatic C-C), 1267, 1100 (C-N), 760, 700 (aromatic C-H). LC-MS (ESI +ve): 356.35 [M+H]+. 73%, White solid, 47-53 °C, 0.2 (10% E/P).
5t 1H NMR (400 MHz, CDCl3) d (ppm): 0.82 (t, 3H), 0.88 (t, 2H), 1.25 - 1.29 (m, 3H), 1.28 - 1.43 (m, 6H), 2.33 (t, 1H), 2.58 (s, 3H), 3.99 (t, 1H), 6.60 (d, 1H), 6.9 (d, 1H), 7.05 - 7.09 (m, 1H), 7.14 (t, 2H), 7.30 (m, 3H), 7.36 (d, 2H), 7.44 (t, 2H); 13C NMR (100 MHz, CDCl3) d (ppm): 14.0, 22.5, 26.1, 28.5, 28.7, 30.5, 31.5, 44.9, 123.9, 126.4, 126.7, 127.9, 128.9, 129.1, 130.3, 130.9, 131.1, 134.2, 136.7, 138.4, 144.3, 149.4, 149.6; FTIR (? cm-1 ): 2923, 2858 (C-H in alkanes), 1451 (C C), 701 (Ar-H); LC-MS (ESI +ve): 98.53 %, 398.46 [M +H]+. 61%, Sticky brown liquid, 0.17 (15% E/P)
5u 1H NMR (400 MHz, CDCl3) d (ppm): 0.83 (t, 3H), 0.99 - 1.58 (m, 14H), 3.87 (t, 5H), 6.19 - 6.21 (m, 1H), 6.36 - 6.37 (m, 1H), 6.77 (t, 1H), 7.13 (t, 1H), 7.20 (t, 2H), 7.39 - 7.52 (m, 7H); 13C NMR (100 MHz, CDCl3) d (ppm): 14.1, 22.6, 26.1, 28.6, 29.1, 29.3, 30.5, 31.8, 44.9, 123.5, 126.4, 126.7, 128.1, 128.3, 128.5, 128.8, 129.1, 130.9, 134.2, 136.7, 144.3, 149.4, 149.6; FTIR (? cm-1): 2926 (C-H in alkanes), 1455 (C C), 704 (Ar-H); LC-MS (ESI +ve): 384.80 [M+H]+. 65%, Brown liquid, 0.18 (10% E/P)
5d’ 1H NMR (400 MHz, CDCl3) d (ppm): 0.75 (t, 3H), 0.86 (br s, 4H), 1.10 – 1.13 (m, 2H), 1.25 (d, 3H), 1.29 – 1.31 (m, 1H), 1.35 – 1.40 (m, 1H), 3.62 (s, 3H) 4.21 (s, 1H), 6.15 (t, 1H), 6.26 – 6.27 (m, 1H), 6.96 (s, 1H), 7.03 (t, 2H), 7.30 – 7.33 (m, 2H), 7.38 (t, 2H), 7.49 (t, 2H); 13C NMR (100 MHz, CDCl3) d (ppm): 13.9, 22.0, 22.4, 26.2, 31.3, 34.8, 35.9, 53.6, 107.5, 112.1, 114.7, 114.9, 115.9 116.1, 122.2, 123.8, 128.0, 128.1, 130.7, 130.7, 133.6, 136.7, 160.3, 161.8, 162.7, 164.3; FTIR (cm-1): 2918 (C-H in alkanes), 1453 (C-C in aromatic), 1358 (C-H in alkane), 725 (C-H in alkenes); LC-MS = m/z = 433.54, observed 434.5 [M+H]+, LC purity 99.78 %. 65%, Greenish blue solid, 85-90 °C, 0.17 (10% E/P)
5e’ 1H NMR (400 MHz, CDCl3) d (ppm): 4.00 (s, 3H), 5.49 – 5.51 (m, 1H), 5.93 (t, 1H), 6.60 (br s, 1H), 6.92 – 6.99 (m, 8H), 7.10 – 7.12 (m, 2H), 7.51 – 7.55 (m, 2H; 13C NMR (100 MHz, CDCl3) d (ppm): 36.5, 44.6, 107.6, 110.8, 114.8, 115.0, 116.2, 116.4, 122.2, 124.4, 127.3, 128.1, 128.9, 130.6, 130.9, 132.6, 136.1, 162.1, 164.6; FTIR (cm-1): 1593 (C-C in aromatic), 1269, 1095 (C-N); LC-MS = m/z = 503.31, observed 504.66 [M+H]+, LC purity 89.37 %. 60%, Brown solid, 144-150 °C, 0.17 (10% E/P)
5g’ LC-MS = m/z = 375.17, observed 376.70 [M+H]+, LC purity 95.5 %.
65%, Brown solid, 85-90 °C, 0.19 (10% E/P)
5h’ LC-MS = m/z = 403.52, observed 404.48 [M+H]+, LC purity 95.60 %.
72%, Pale brown solid, 88-92 °C, 0.18 (10% E/P)
5i’ LC-MS = m/z = 445.60, observed 446.59 [M+H]+, LC purity 94.72 %.
80%, Pale brown gummy liquid, 0.23 (10% E/P)
5j’ LC-MS = m/z = 487.30, observed 488.60 [M+H]+, LC purity 92.96 %.
75%, Brown liquid, 0.19 (10% E/P)

General procedure for the synthesis of 5b, 5f-5i, 5s, 5w-5z and 5a’-5c’
5a, 5k, 5q, 5v and 5f’ (0.33 mmol), alkylating agent (1.0 mmol), K2CO3 (1.0 mmol), and acetonitrile (10 mL) are mixed, and heated at 85-90 °C, the reaction was stirred overnight. TLC was employed to monitor the reaction's progress. After the completion of the reaction, the solvent was vacuum-vaporized, the obtained semi-solid was diluted with water, extracted using ethyl acetate, dried over Na2SO4, filtered, and distilled to obtain the crude. The crude product was purified using ethyl acetate/petroleum ether column chromatography on silica gel (60-120 mesh size) to get N-alkylated products as shown in Table 8 below:

Table 8. Structure, characterization and other details of compounds 5b, 5f-5i, 5s, 5w-5z and 5a’-5c’
Compound Compound code Analytical data Yield, Appearance, mp, Rf

5b 1H NMR (400MHz, CDCl3) d (ppm): 0.61-0.65 (t, 3H), 1.28-1.31 (s, 3H), 1.41-1.45 (m, 4H), 2.30 (s, 3H), 2.47 (s, 3H), 3.86-3.89 (t, 2H), 7.04-7.05 (d, 3H), 7.29-7.31 (m, 5H), 7.42-7.47 (m, 4H), 8.09-8.10 (d, 1H), 8.70 (d, 1H), 8.97 (s, 1H). 13C NMR (101MHz, CDCl3) d: 10.8, 21.1, 21.4, 24.0, 46.4, 47.1, 123.5, 126.6, 127.9, 128.0, 128.8, 129.8, 130.0, 130.7, 131.4, 135.9, 136.7, 138.6, 144.1, 149.4, 149.5: FTIR (cm-1): 3031 (Ar-H), 2923 (-CH str in CH3), 2862 (CH aliph.), 1574 (C=N), 1453 (C=C), 1022 (C-N), 813, 710 (Ar-H). MS (ESI +ve): 367.15 (M+).
58%, Yellow solid. 112-113 °C, 0.20; (50% E/P)

5f 1H NMR (400MHz, CDCl3) d (ppm): 0.81-.084 (t, 3H), 0.92-0.99 (m, 3H), 1.15-1.22 (m, 2H), 1.25-1.29 (d, 2H), 1.41-1.42 (d, 1H), 1.71 (s, 11H), 2.28 (1H, 2H), 2.44 (s, 2H), 3.85-3.89 (t, 2H), 7.39-7.47 (d, 2H), 7.28 (s, 3H), 7.39-7.47 (m, 3H), 8.05-8.08 (t, 1H), 8.66-8.68 (d, 1H), 8.93-8.94 (d, 1H). 13C NMR (100 MHz, CDCl3) d: 14.0, 21.1, 21.4, 22.5, 26.1, 27.7, 28.0, 28.5, 28.7, 30.5, 31.6, 44.8, 123.5, 123.8, 123.8, 126.6, 128.1, 128.8, 129.8, 130.8, 136.7, 138.6, 143.4. FTIR (cm-1): 3018 (Ar-H), 2925 (-CH str in CH3), 2857 (CH aliph.), 1616 (C=N), 1459 (C=C), 1028 (C-N), 823, 721 (Ar-H). MS (ESI +ve): 465.05 (M+).
59%, Brown thick oil, 0.25 (50% E/P)

5g 1H NMR (400MHz, CDCl3) d (ppm): 0.89-0.9 (d, 5H), 1.28-1.31 (d, 29H), 2.30 (s, 2H), 2.47 (s, 1H), 3.87-3.91 (t, 1H), 7.04-7.05 (d, 1H), 7.29-7.31 (d, 2H),7.42-7.47 (m, 1H), 8.08-8.10 (d, 1H), 8.70 (d, 1H), 8.97 (s,1H). 13C NMR (101 MHz, CDCl3): 14.1, 21.1, 21.4, 22.7, 26.1, 28.6, 29.1, 29.3, 29.4, 29.5, 29.6, 29.6, 30.5, 31.9, 44.8, 123.5, 126.6, 127.9, 128.1, 128.8, 129.8, 130.0, 130.8, 131.5, 135.9, 136.7, 138.3, 138.6, 144.0, 149.4, 149.5: FTIR (cm-1): 3026 (Ar-H), 2923 (-CH str in CH3), 2854 (CH aliph.), 1569 (C=N), 1462 (C=C), 1022 (C-N), 824, 717 (Ar-H). MS (ESI +ve): 493.35 (M+).

64%, Brown thick oil. (50% E/P)

5h 1H NMR (400MHz, CDCl3) d (ppm): 0.90 (s, 4H), 0.98 (s, 5H), 1.27-1.30 (s, 21H), 2.30 (s, 3H), 2.47 (s, 3H), 3.88-3.91 (t, 2H), 7.04-7.05 (d, 2H), 7.31 (s, 4H), 7.47-7.44 (d, 3H), 8.08-8.10 (d, 1H), 8.70 (s, 1H), 8.97 (s, 1H). 13C NMR (101 MHz, CDCl3): 14.1, 21.1, 21.4, 22.7, 26.1, 28.6, 29.1, 29.3, 29.4, 29.5, 29.6, 29.6, 30.5, 31.9, 44.8, 123.5, 126.6, 127.9, 128.1, 128.8, 129.8, 130.0, 130.8, 131.5, 135.9, 136.7, 138.3, 138.6, 144.0, 149.4, 149.5: FTIR (cm-1): 3026 (Ar-H), 2923 (-CH str in CH3), 2854 (CH aliph.), 1569 (C=N), 1462 (C=C), 1022 (C-N), 824, 717 (Ar-H). MS (ESI +ve): 521.05 (M+).
58%, Brown thick oil, 0.27 (50% E/P)

5i 1H NMR (400MHz, CDCl3) d (ppm): 0.90 (s, 4H), 0.98-1.04 (s, 7H), 1.27-1.43 (s, 23H), 2.30 (s, 3H), 2.47 (s, 3H), 3.88-3.91 (t, 2H), 7.04-7.05 (d, 2H), 7.31 (s, 4H), 7.42-7.44 (d, 1H), 8.08-8.10 (d, 1H), 8.70 (s, 1H), 8.97 (s, 1H). 13C NMR (101 MHz, CDCl3) 14.1, 21.1, 21.4, 21.7, 22.7, 26.1, 29.1, 29.3, 29.4, 29.5, 29.6, 29.7, 30.5, 31.8, 31.9, 45.1, 126.6, 127.9, 128.1, 128.8, 129.8, 130.0, 130.8, 131.5, 131.5, 133.1, 135.9, 136.7, 138.6, 144.0, 149.4, 149.5: FTIR (cm-1): 2919 (-CH str in CH3), 2851 (CH aliph.), 1665 (C=N), 1455 (C=C), 1022 (C-N), 817, 715 (Ar-H). MS (ESI +ve): 549.35 (M+).
56%, Brown thick oil. 0.26 (50% E/P).

5s 1H NMR (400 MHz, CDCl3) d (ppm): 0.70 (t, 3H), 0.95 - 1.00 (m, 2H), 1.03 - 1.07 (m, 2H), 1.33 - 1.39 (m, 2H), 3.85 (s, 3H), 3.87 (t, 2H), 6.20 (t, 1H), 6.37 (d, 1H), 6.77 (t, 1H), 7.10 - 7.20 (m, 3H), 7.40 (d, 2H), 7.45 - 7.52 (m, 5H); 13C NMR (100 MHz, CDCl3) d (ppm): 13.7, 21.8, 28.3, 30.1, 35.3, 44.6, 107.5, 110.8, 124.2, 126.2, 126.6, 127.9, 128.3, 128.9, 131.0, 131.6, 140.4; FTIR (cm-1): 1593 (C-C in aromatic), 1269, 1095 (C-N); LC-MS (ESI +ve): 370.45 [M+H]+.
89%, Greenish blue solid, 47-54 °C, 0.17 (10% E/P).

5w 1H NMR (400 MHz, CDCl3) d (ppm): 0.96 (t, 3H), 3.79 (s, 3H), 3.87 (q, 2H), 6.16 (t, 1H), 6.41 (q, 1H), 6.98 (s, 1H), 7.07 (t, 2H), 7.41 – 7.37 (m, 4H), 7.55 – 7.51 (m, 2H); 13C NMR (100 MHz, CDCl3) d (ppm): 16.3, 35.4, 39.5, 107.6, 110.8, 114.8, 115.0, 116.2, 116.4, 122.2, 124.5, 127.4, 128.0, 128.1, 130.7, 130.7, 132.8, 137.0, 162.8, 164.2; FTIR (cm-1): 2923, 2953 (C-H in aromatic), 1454 (C-C in aromatics), 1361 (C-H in alkanes), 751, 720 (C-H in alkenes); LC-MS = m/z = 363.15, observed 364.4 [M+H]+, LC purity 98.90 %.
62%, White solid, 95-98 °C, 0.12 (10% E/P).

5x 1H NMR (400 MHz, CDCl3) d (ppm): 0.68 (t, 3H), 1.01 – 1.07 (m, 2H), 1.30 – 1.35 (m, 2H), 3.84 (s, 3H), 3.86 (t, 2H), 6.20 (t, 1H), 6.36 – 6.37 (m, 1H), 6.78 (t, 1H), 6.89 (t, 2H), 7.19 (t, 2H), 7.35 – 7.39 (m, 2H), 7.42 – 7.46 (m, 2H); 13C NMR (100 MHz, CDCl3) d (ppm): 13.3, 19.4, 29.7, 35.3, 44.4, 107.6, 110.9, 114.8, 115.0, 116.2, 116.4, 122.2, 124.4, 127.4, 128.1, 128.2, 130.7, 130.7, 132.8, 136.9, 162.8, 164.1; FTIR (cm-1): 2921 (C-H in aromatic), 1263 (C-N in aromatic amine), 802, 728 (C-H in alkenes); LC-MS = m/z = 391.19, observed 392.51 [M+H]+, LC purity 99.68 %.
60%, Pale brown solid, 101-105 °C, 0.16 (10% E/P)

5y 1H NMR (400 MHz, CDCl3) d (ppm): 0.77 (t, 3H), 0.99 – 1.01 (m, 4H), 1.33 – 1.37 (m, 2H), 3.84 (s, 3H), 3.85 – 3.87 (m, 2H), 6.21 (t, 1H), 6.35 – 6.37 (m, 1H), 6.78 (s, 1H), 6.89 (t, 2H), 7.19 (t, 2H), 7.35 – 7.39 (m, 2H), 7.43 – 7.46 (m, 2H); 13C NMR (100 MHz, CDCl3) d (ppm): 13.8, 22.3, 25.9, 30.4, 30.9, 35.3, 44.6, 107.6, 110.8, 114.8, 115.0, 116.2, 116.4, 122.3, 124.4, 127.4, 128.1, 128.1, 130.7, 130.8, 132.8, 136.9, 162.8, 164.1; FTIR (cm-1): 2944 (C-H in aromatic), 1219 (C-N in aromatic amine), 811, 719 (C-H in alkenes); LC-MS = m/z = 419.22, observed 420.41 [M+H]+, LC purity 98.14 % 60%, White solid, 81-85 °C, 0.15 (10% E/P)

5z 1H NMR (400 MHz, CDCl3) d (ppm): 0.84 (t, 3H), 1.01 – 1.09 (m, 4H), 1.11 – 1.19 (m, 3H), 1.21 – 1.23 (m, 2H), 1.35 – 1.37 (m, 2H), 3.83 (s, 3H), 3.83 – 3.87 (m, 2H), 6.19 – 6.21 (m, 1H), 6.35 – 6.36 (m, 1H), 6.77 – 6.78 (m, 1H), 6.88 (t, 2H), 7.17 (t, 2H), 7.35 – 7.39 (m, 2H), 7.43 – 7.46 (m, 2H); 13C NMR (100 MHz, CDCl3) d (ppm): 14.0, 22.5, 26.1, 28.6, 28.9, 30.4, 31.6, 35.3, 44.6, 107.6, 110.8, 114.8, 115.0, 116.2, 116.4, 122.2, 124.4, 127.4, 128.1, 128.2, 130.7, 130.7, 132.8, 136.9, 162.8, 164.1; FTIR (cm-1): 2923 (C-H in aromatic), 1569, 1497 (C-C in aromatic), 837, 716 (C-H in alkenes); LC-MS = m/z = 447.25, observed 448.24 [M+H]+, LC purity 98.50 %.
77%, Pale brown solid, 75-78 °C, 0.18 (10% E/P)

5a’ 1H NMR (400 MHz, CDCl3) d (ppm): 0.87 (t, 3H), 1.00 – 1.34 (m, 17H), 3.83 (s, 3H), 3.83 – 3.87 (m, 2H), 6.20 (t, 1H), 6.77 (br s, 1H), 6.81 (t, 2H), 7.18 (t, 2H), 7.35 – 7.39 (m, 2H), 7.43 – 7.46 (m, 2H); 13C NMR (100 MHz, CDCl3) d (ppm): 14.1, 22.6, 26.1, 28.7, 29.2, 30.4, 31.8, 35.3, 44.6, 107.6, 110.8, 114.8, 115.0, 116.2, 116.4, 122.2, 124.4, 127.4, 128.1, 128.2, 130.7, 130.8, 132.8, 136.9, 162.8, 164.1; FTIR (cm-1): 2925 (C-H in aromatic), 1501 (C-C in aromatic), 837, 714 (C-H in alkenes); LC-MS = m/z = 475.28, observed 476.62 [M+H]+, LC purity 88.61 %. 95%, Pale brown solid, 73-75 °C 0.18 (10% E/P)

5b’ 1H NMR (400 MHz, CDCl3) d (ppm): 0.89 (t, 5H), 0.99 – 1.01 (m, 3H), 1.24 – 1.25 (m, 12H), 1.70 (s, 2H), 3.83 (s, 3H), 6.19 – 6.21 (m, 1H), 6.35 – 6.36 (m, 1H), 6.77 – 6.78 (m, 1H), 6.89 (t, 2H), 7.18 (t, 2H), 7.35 -7.38 (m, 2H), 7.42 – 7.46 (m, 2H); 13C NMR (100 MHz, CDCl3) d (ppm): 14.1, 22.6, 26.1, 28.7, 29.2, 29.3, 29.4, 29.5, 29.6, 29.7, 30.4, 31.9, 35.3, 44.6, 107.6, 110.8, 114.8, 115.0, 116.2, 116.4, 122.2, 124.4, 127.3, 128.1, 128.1, 130.7, 130.7, 132.8, 136.9, 162.8, 164.1; FTIR (cm-1): 2923 (C-H in aromatic), 2854 (C-H in alkanes), 1510 (C-C in aromatic), 1225 (C-N aromatic amines) 831, 717 (C-H in alkenes); LC-MS = m/z = 503.31, observed 504.66 [M+H]+, LC purity 89.37 %.
88%, Dark brown liquid, 0.2 (10% E/P)

5c’ 1H NMR (400 MHz, CDCl3) d (ppm): 0.87 (t, 4H), 1.00 – 1.01 (m, 4H), 1.25 (m, 19H), 1.70 (s, 2H), 3.83 (s, 3H), 3.83 – 3.87 (m, 2H), 6.19 – 6.21 (m, 1H), 6.35 – 6.36 (m, 1H), 6.77 – 6.78 (m, 1H), 6.89 (t, 2H), 7.18 (t, 2H), 7.35 -7.38 (m, 2H), 7.42 – 7.46 (m, 2H); 13C NMR (100 MHz, CDCl3) d (ppm): 14.1, 22.7, 26.1, 28.7, 29.2, 29.3, 29.4, 29.5, 29.6, 29.6, 30.4, 31.9, 35.3, 44.6, 107.6, 110.8, 114.8, 115.0, 116.2, 116.4, 122.2, 124.4, 127.3, 128.1, 128.1, 130.7, 130.7, 132.8, 136.9, 162.8, 164.1; FTIR (cm-1) 2922 (C-H in aromatic), 2853 (C-H in alkanes), 1509 (C-C in aromatic), 838, 717 (C-H in alkenes); LC-MS = m/z = 531.34, observed 532.83 [M+H]+, LC purity 99.01 %.
60%, Brown liquid, 0.17 (10% E/P)
,CLAIMS:We claim
1. A method of synthesizing a compound of formula (I):

R1=3-pyridyl, 3-Indolyl, 2-N-methyl pyrrole, 3-Quinoline. R2=H, Methyl, Fluoro. R3= ethyl, propyl, butyl, pentyl, heptane-2-yl, octyl, decyl, dodecyl, tetradecyl, hexadecyl, 1-(Z)-octadec-5-enyl, p-fluoro phenyl.
wherein:
R1, R2, and R3 are independently selected from the group consisting of hydrogen, alkyl, aryl, heteroaryl, fluoro, and substituted derivatives thereof;
comprising:
a) reacting a diketone of formula (2)

a) heterocyclic aldehyde of formula, ammonium acetate, and/or amine in the presence of a catalyst in a solvent at predefine temperature; and
b) optionally, alkylating the compound obtained in step (a) with an alkylating agent selected from the group consisting of 1-iodoethane, 1-bromopropane, 1-iodobutane, 1-bromopentane, 1-iodohexane, 1-bromooctane, 1-iododecane, 1-iodododecane, 1-bromotetradecane, and 1-bromohexadecane in a solvent comprising acetonitrile in the presence of a base selected from the group consisting of K2CO3 and Na2CO3 at a temperature of 85-90 °C.
2. The method to synthesize the compound, as claimed in claim 1 wherein the solvent comprises a primary alcohol such as methanol or ethanol or combination of methanol and ethanol.
3. The method to synthesize the compound, as claimed in claim 1, wherein the catalyst is selected from iodine or FeCl3.
4. The method to synthesize the compound, as claimed in claim 1, wherein reaction mixture is heated at a predefine temperature, wherein said pre-defined temperature is 78 - 85 °C.
5. The method as claimed in claim 1 wherein said amine is selected from the group consisting of 1-methyl amine, 1-ethyl amine, 1-butyl amine, 1-pentyl amine, 1-heptan-2-yl amine, 1-octyl amine, and 1-(Z)-octadec-5-enyl amine.
6. The compounds as derived from a method as claimed in claim 1, wherein said compounds are as follows:
compound represented by formula A

compound represented by formula B
compound represented by formula C
compound represented by formula D
compound represented by formula E
A compound represented by formula F
compound represented by formula G
compound represented by formula H
compound represented formula I
compound represented by formula J

7. The compounds of formula A and B as claimed in claim 6 wherein said compounds when subject to in vitro analysis against various breast cancer cell lines, wherein results are in the range of 35 to 50 µM.
8. The compounds of formula A and B as claimed in claim 6 when subjected to in vivo animal studies wherein 50-60% of tumor volume is reduced compared to standard cisplatin.
9. The compounds of formula C and D as claimed in claim 6 wherein said compounds show in vitro analysis against various cancer cell lines, wherein results range from 4.26 to 37.43 µM.
10. The compounds of formula E and F as claimed in claim 6, wherein these compounds are evaluated through in vitro analysis against a variety of breast cancer cell lines, yielding results within the concentration range of 25 to 50 µM.
11. The compounds as claimed in claim 6 wherein said compounds when subject to in vitro analysis against the normal cell line, that is L929 cell line (mouse fibroblast cell line), show the results that the molecules are less toxic to normal cells.