TECHNICAL FIELD
The present invention relates to thionated cinnamate compounds and process of preparation thereof.
BACKGROUND
Cinnamic esters are immensely important organic compounds due to their application in a wide range of industrial products such as plasticizers, graphics, lubricants, flavours, perfumes and cosmetics. For example, 2-ethylhexyl-4-methoxycinnamate is a UV absorbing sunscreen agent and a common ingredient in most of the new sunscreen lotions and many other cosmetic formulations. Further, cinnamic esters possess various pharmacological activities including antioxidant, antimicrobial and anticancer activities. However, these esters do not exhibit high potency.
Cell adhesion molecules are key regulators of leukocytes trafficking to sites of inflammation. Various inflammatory mediators, for example cytokines like TNF-a (tumor necrosis factor a), IL-ip and bacterial lipopolysaccharide, increase the expression of cell adhesion molecules namely ICAM-l(intercellular adhesion molecule-1), VCAM-l(vascular cell adhesion molecule-1) and E-selectin on the endothelial cells. A critically regulated expression of cell adhesion molecules is therefore essential for maintaining the normal homoeostasis. The cytokine induced activation of ICAM-1, VCAM-1 and E-selectin takes place at the transcriptional activation of these genes. Inhibition of cell adhesion molecules has been shown to be a useful therapeutic approach to regulate inflammatory response. Monoclonal antibodies(mAbs) specific to cell adhesion molecules and small molecules from natural sources and synthetic routes have been used successfully for downregulating the induced expression of cell adhesion molecules both in vitro and in vivo. However, treatment with mAbs is found to be limited because of problems

with endotoxin contamination, secondary antibody formation, serum sickness and anaphylaxis.
Accordingly, to overcome the problem encountered in the prior art the inventors of the present invention provide thionated cinnamate compounds as described herein below.
OBJECT AND SUMMARY
The principal object of the present invention is to provide thionated cinnamate compounds which are more potent than the naturally occurring candidates.
Another object of the present invention is to provide thionated cinnamate compounds which can be used for the treatment of inflammatory diseases such as asthma and Chronic Obstructive Pulmonary Disease.
The present invention provides thionated cinnamate compound of formula I:
(Formula Removed)
wherein
(Formula Removed)
M represents c=c or orc=c;
X represents O or S;
Y represents OR7, SR7 or NR8R9;

R1-R6 each independently represents H, (CH2)nOH, (CH2)nSH, (CH2)nhalogen,alkyl, (CH2)naryl, (CH2)nOalkyl, (CH2)nSalkyl/ (CH2)nCOalkyl, (CH2)nCSalkyl,
(CH2)nCOOH, (CH2)nCOOalkyl, (CH2)nC00aryl, (CH2)nCOSalkyl/
(CH2)nCSOalkyl, (CH2)nCOSaryl, (CH2)nCSOaryl, (CH2)nNH2, (CH2)nNHalkyl, (CH2)nN(alkyl)2/ (CH2)nNHacyl, (CH2)nCN, (CH2)nNO2; R7 can be H, alkyl, (CH2)naryl;
R8, R9 each independently represents H, alkyl, (CH2)naryl; R10-R14 each independently represents H, alkyl, aryl, Oalkyl, Oaryl, OCO alkyl, OCO aryl, amino or substituted amino, (CH2)nhalogen, (CH2)naryl, (CH2)nOH, (CH2)nSH, (CH2)nOalkyl, (CH2)nSalkyl, (CH2)nOaryl, (CH2)nSaryl, (CH2)nNH2, (CH2)nNHalkyl, (CH2)nN(alkyl)2, (CH2)nNHacyl, (CH2)nCN, (CH2)nN02, (CH2)nCOOH, (CH2)nCSOH, (CH2)nCOSH, (CH2)nCOOalkyl, (CH2)nCOOaryl,
(CH2)nCSOalkyl, (CH2)nCOSaryl, (CH2)nCOSalkyl, (CH2)nCSOaryl, (CH2)nCONH2,
(CH2)nCONHalkyl, (CH2)nCON(alkyl)2, R7-c-z-(CH2)n-/ R7-(CH2)n.
Z can be 0, S or NR7;
n represents 0-5.
including pharmaceutically acceptable optical and geometrical isormers or
salts.
The present invention further relates to a process for the preparation of thionated cinnamates as mentioned below:
a) adding sulphonylating agent such as diphosphorus pentasulphide and an organic solvent like anhydrous dioxane to a compound of formula II
(Formula Removed)
wherein

(Formula Removed)
M represents c=c or R4 Re or c=c;
Y represents OR7, SR7 or NRsRg;
R1-R6 each independently represents H, (CH2)nOH, (CH2)nSH, (CH2)nhalogen/
alkyl, (CH2)naryl, (CH2)nOalkyl, (CH2)nSalkyl, (CH2)nCOalkyl, (CH2)nCSalkyl,
(CH2)nCOOH, (CH2)nCOOalkyl, (CH2)nCOOaryl, (CH2)nCOSalkyl,
(CH2)nCSOalkyl/ (CH2)nCOSaryl, (CH2)nCSOaryl, (CH2)nNH2/ (CH2)nNHalkyl,
(CH2)nN(alkyl)2, (CH2)nNHacyl, (CH2)nCN, (CH2)nN02;
R7 can be H, alkyl, (CH2)naryl;
Rs, R9 each independently represents H, alkyl, (CH2)naryl;
R10-R14 each independently represents H, alkyl, aryl, Oalkyl, Oaryl, OCO alkyl,
OCOaryl, amino or substituted amino, (CH2)nhalogen, (CH2)naryl, (CH2)nOH,
(CH2)nSH, (CH2)nOalkyl, (CH2)nSalkyl, (CH2)nOaryl, (CH2)nSaryl, (CH2)nNH2,
(CH2)nNHalkyl, (CH2)nN(alkyl)2, (CH2)nNHacyl, (CH2)nCN, (CH2)nN02,
(CH2)nCOOH, (CH2)nCSOH, (CH2)nCOSH, (CH2)nCOOalkyl, (CH2)nCOOaryl,
(CH2)nCSOalkyl, (CH2)nCOSaryl, (CH2)nCOSalkyl, (CH2)nCSOaryl, (CH2)nCONH2,
(CH2)nCONHalkyl, (CH2)nCON(alkyl)2, R7-C-Z-(CH2)„-/ R7-(CH2)-Z-C-;
Z can be 0, S or NR7; n represents 0-5. and;
b) heating the resultant mixture of step (a) to obtain thionated cinnamates.
BRIEF DESCRIPTION OF DRAWINGS
The aforementioned aspects and other features of the present disclosure will be explained in the following description, taken in conjunction with the accompanying examples and drawings.
Figure 1 depicts the concentration dependent inhibition of TNF-a induced ICAM-1, VCAM-1 and E-selectin expression by Ethyl 3',4',5'-trimethoxythionocinnamate (ETMTC).

Figure 2 depicts the flow cytometric analysis of inhibition of TNF-α induced ICAM-1, VCAM-1 and E-selectin expression by ETMTC.
Figure 3 depicts the inhibition of adhesion of neutrophils to endothium monolayer by ETMTC in a concentration dependent manner.
While the disclosure will be described in conjunction with the illustrated embodiments, it will be understood that it is not intended to limit the disclosure to such embodiments. On the contrary, it is intended to cover all alternatives, modifications and equivalents as may be included within the spirit and scope of the disclosure as defined by the appended claims.
DETAILED DESCRIPTION
The embodiments of the present disclosure will now be described in detail with reference to the accompanying drawings and examples. However, the present disclosure is not limited to the embodiments. The present disclosure can be modified in various forms. Thus, the embodiments of the present disclosure are only provided to explain more clearly the present disclosure to the ordinarily skilled in the art of the present disclosure.
Cell adhesion molecules mediate recruitment of leukocytes through endothelial monolayer in number of inflammatory diseases like asthma, arthritis etc. Thus, these cell adhesion molecules are thought to be attractive and feasible strategy for the treatment of inflammatory diseases such as asthma and chronic obstructive pulmonary disease.
Thio and thiono analogs of cinnamic acid esters are potent inhibitor of cell adhesion molecules i.e. ICAM-1 expression on human endotherlial cells. The structure activity studies indicate that the chain length of the alcohol moiety, substituent in the aromatic ring and α, ß-double bond of the thiocinnamates

have significant effect on the inhibition of TNF- a induced expression of ICAM-1 on the endothelial cells.
Thionated cinnamates have been found to significantly inhibit the TNF-a induced expression of ICAM-1 on human endothelial cells in a concentration dependent manner. It has been observed that thio analogs exhibit better activity than the corresponding oxygenated compound. Ethyl 3'4,5'-trimethoxythionocinnamate (29) is working at 50 % less concentration as compared to ethyl 3,4,5'-trimethoxycinnamate.
The present invention provides thionated cinnamate compound of formula I:
(Formula Removed)
wherein
(Formula Removed)
M represents c=c or orc=c;
X represents O or S;
Y represents OR7/ SR7 or NRsRg;
R1-R6 each independently represents H, (CH2)nOH, (CH2)nSH, (CH2)nhalogen,
alkyl, (CH2)naryl, (CH2)nOalkyl, (CH2)nSalkyl, (CH2)nCOalkyl, (CH2)nCSalkyl,
(CH2)nCOOH, (CH2)nCOOalkyl, (CH2)nCOOaryl, (CH2)nCOSalkyl,
(CH2)nCSOalkyl, (CH2)nCOSaryl, (CH2)nCSOaryl (CH2)nNH2/ (CH2)nNHalkyl,
(CH2)nN(alkyl)2/ (CH2)nNHacyl, (CH2)nCN, (CH2)nNO2;
R7 can be H, alkyl, (CH2)naryl;
Rs, R9 each independently represents H, alkyl, (CH2)naryl;
R10-R14 each independently represents H, alkyl, aryl, Oalkyl, Oaryl, OCO alkyl,
OCO aryl, amino or substituted amino, (CH2)nhalogen, (CH2)naryl, (CH2)nOH,

(CH2)nSH, (CH2)nOalkyl, (CH2)nSalkyl, (CH2)nOaryl, (CH2)nSaryl, (CH2)nNH2, (CH2)nNHalkyl, (CH2)nN(alkyl)2, (CH2)nNHacyl, (CH2)nCN, (CH2)nNO2/ (CH2)nCOOH, (CH2)nCSOH, (CH2)nCOSH, (CH2)nCOOalkyl, (CH2)nC00aryl, (CH2)nCSOalkyl, (CH2)nCOSaryl, (CH2)nCOSalkyl, (CH2)nCSOaryl, (CH2)nCONH2/
(CH2)nCONHalkyl/ (CH2)nCON(alkyl)2;
Z can be O, S or NR7;
n represents 0-5.
including pharmaceutically acceptable optical and geometrical isormers or
salts.
In a specific embodiment of the invention the thionated cinnamate compound of formula I is defined as follows:
M represents -CH=CH- or -CH2-CH2-;
X represents O or S;
Y represents OR7 or SR7;
R7 can be alkyl, (CH2)naryl;
R10-R14 each independently represents alkyl, aryl, Oalkyl, Oaryl, OCO alkyl,
OCOaryl, amino or substituted amino.
Synthesis of Thionated Cinnamates
The thionated cinnamates of the present invention are prepared by
a) adding sulphonylating agent such as diphosphorus pentasulphide and
an organic solvent like anhydrous dioxane to a compound of formula II
(Formula Removed)
wherein

M represents
Y represents OR7, SR7 or NR8R9;
R1-R6 each independently represents H, (CH2)nOH, (CH2)nSH, (CH2)nhalogen,
alkyl, (CH2)naryl, (CH2)nOalkyl, (CH2)nSalkyl, (CH2)nCOalkyl, (CH2)nCSalkyl,
(CH2)nCOOH, (CH2)nCOOalkyl, (CH2)nCOOaryl, (CH2)nCOSalkyl,
(CH2)nCSOalkyl/ (CH2)nCOSaryl, (CH2)nCSOaryl, (CH2)nNH2/ (CH2)nNHalkyl/
(CH2)nN(alkyl)2, (CH2)nNHacyl, (CH2)nCN, (CH2)nNO2;
R7 can be H, alkyl, (CH2)naryl;
R8, R9 each independently represents H, alkyl, (CH2)naryl;
R10-R14 each independently represents H, alkyl, aryl, Oalkyl, Oaryl, OCO alkyl,
OCO aryl, amino or substituted amino, (CH2)nhalogen, (CH2)naryl, (CH2)nOH,
(CH2)nSH, (CH2)nOalkyl, (CH2)nSalkyl, (CH2)nOaryl, (CH2)nSaryl, (CH2)nNH2,
(CH2)nNHalkyl, (CH2)nN(alkyl)2, (CH2)nNHacyl, (CH2)nCN, (CH2)nNO2,
(CH2)nCOOH, (CH2)nCSOH, (CH2)nCOSH, (CH2)nCOOalkyl, (CH2)nCOOaryl,
(CH2)nCSOalkyl, (CH2)nCOSaryl, (CH2)nCOSalkyl, (CH2)nCSOaryl, (CH2)nCONH2,
(CH2)nCONHalkyl, (CH2)nCON(alkyl)2,(Formula Removed) Z can be O, S or NR7; n represents 0-5. and;
b) heating the resultant mixture of step (a) to obtain thionated cinnamates.
The compound of formula II is prepared by neutralizing the reaction mixture obtained by heating a mixture of compound of formula III
wherein

M represents (Formula Removed)
R1-R6 each independently represents H, (CH2)nOH, (CH2)nSH, (CH2)nhalogen,
alkyl, (CH2)naryl, (CH2)nOalkyl, (CH2)nSalkyl, (CH2)nCOalkyl, (CH2)nCSalkyl,
(CH2)nCOOH, (CH2)nCOOalkyl/ (CH2)nC00aryl, (CH2)nCOSalkyl,
(CH2)nCSOalkyl, (CH2)nCOSaryl, (CH2)nCSOaryl, (CH2)nNH2/ (CH2)nNHalkyl,
(CH2)nN(alkyl)2, (CH2)nNHacyl, (CH2)nCN, (CH2)nNO2;
R7 can be H, alkyl, (CH2)naryl;
R8, R9 each independently represents H, alkyl, (CH2)naryl;
R10-R14 each independently represents H, alkyl, aryl, Oalkyl, Oaryl, OCO alkyl,
OCOaryl, amino or substituted amino, (CH2)nhalogen, (CH2)naryl, (CH2)nOH,
(CH2)nSH, (CH2)nOalkyl, (CH2)nSalkyl, (CH2)nOaryl, (CH2)nSaryl, (CH2)nNH2,
(CH2)nNHalkyl, (CH2)nN(alkyl)2, (CH2)nNHacyl, (CH2)nCN, (CH2)nN02,
(CH2)nCOOH, (CH2)nCSOH, (CH2)nCOSH, (CH2)nCOOalkyl, (CH2)nCOOaryl,
(CH2)nCSOalkyl, (CH2)nCOSaryl, (CH2)nCOSalkyl, (CH2)nCSOaryl, (CH2)nCONH2,
(CH2)nCONHalkyl,(CH2)nCON(alkyl)2,(Formula Removed) Z can be O, S or NR7; n represents 0-5.
The scheme of the aforementioned reaction process is explained below:
(Formula Removed)

The present invention will now be discussed with reference to the following examples.
EXAMPLES
1. Synthesis of Thio Esters:
A mixture of carboxylic acid (3 mmol), thiol (3.1 mmol) and polyphosphate ester (PPE) (2 ml) was stirred at room temperature for 0.5-11 h. After completion of the reaction, the mixture was treated with saturated aqueous sodium hydrogen carbonate solution (20 ml), and extracted with chloroform (3x20 ml). The combined chloroform extract was dried with sodium sulfate and evaporated in a rotary vacuum evaporator. The crude compounds were passed through a column packed with silica gel in pure petroleum ether to yield the desired compounds as colorless viscous oils in 93-98% yield. The structures of all the esters were unambiguously established on the basis of their spectral (IR, 1H-, 13C NMR spectra and HRMS) analysis. The structures of known esters 13, 16, 22, 24 and 25 were further confirmed by comparison of their physical / spectral data with those reported in the literature (12-15). The yields, and HRMS data of all known compounds are given in Table 4.
2. Synthesis of thiono esters:
The starting ester compounds were prepared from the corresponding acids and alcohols (12) and these esters were freshly recrystallized prior to their use. The solvent dioxane was freshly dried and distilled. A mixture of ester (100 mg), P2S5 and anhydrous dioxane (10 ml) was refluxed until the TLC analysis showed optimum conversion. The crude reaction product was poured in ice-cold water and extracted with ethyl acetate (3 x 30 ml). The organic layer was dried over sodium sulfate and evaporated in vacuo, and the residual oil was chromatographed on a silica gel column using petroleum ether. All the

esters were identified on the basis of their spectral (IR, 1H-, 13C NMR spectra and HRMS) analysis. The structures of known esters 29 and 33 were further confirmed by comparison of their physical / spectral data with those reported in the literature {17,18) respectively.
3. Synthesis of Thiocinnamates
A mixture of cinnamic acid / substituted cinnamic acid / dihydrocinnamic acid (5 mmol), and corresponding alcohol / thioalcohol (25 ml) and concentrated sulphuric acid (0.2 ml) was refluxed for 4-5 h. On completion as observed from TLC examination, the reaction mixture was neutralized by addition of 10 % aqueous sodium hydrogen carbonate solution (w /v) and then extracted with chloroform (2 x 25 ml). Organic layer was separated and dried over anhydrous Na2SO4. The crude product obtained after evaporation of organic solvent was loaded on a small silica gel column and eluted with chloroform to obtain the pure esters / thioesters in 86-100 % yields. The structures of all the esters were unambiguously established on the basis of their spectral (IR, 1H-, 13C NMR spectra and HRMS) data analysis.
4. Synthesis of Thionated Cinnamates
Mixture of freshly crystallized ester / thioester (100 mg), excess of P2S5 and anhydrous dioxane (10 ml) was refluxed until TLC analysis showed optimum conversion. The crude reaction product was poured in ice-cold water and extracted with ethyl acetate (3 x 30 ml). The organic layer was dried with sodium sulfate and evaporated in vacuo, and the residual oil was chromatographed on a silica gel column using petroleum ether. All the thionated cinnamates were identified on the basis of their spectral (IR, 1H-, 13C NMR spectra and HRMS) data analysis.

RESULTS
Cinnamates, thiocinnamates and thionocinnamates are non-toxic to endothelial cells:
To examine the effect of cinnamates, thiocinnamates and thionocinnamates on the viability of endothelial cells, endothelial cells were incubated with these compounds. The viability of endothelial cells as determined by trypan blue exclusion test and was further confirmed by MTT assay as described in "methods". As shown in Tables 1, 2 and 3, the maximum concentration of these compounds was not toxic to the endothelial cells. The concentration for further experiments were chosen where around 95 % cells were viable
Cinnamates, thiocinnamates and thionocinnamates inhibit TNF-α induced expression of ICAM-1 on endothelial cells
The effect of cinnamates, thiocinnamates and thionocinnamates on TNF-a induced expression of ICAM-1 was examined on endothelial cells. Briefly, endothelial cells were incubated with or without cinnamates, thiocinnamates and thionocinnamates at various concentrations for 2 hours prior to induction with TNF- a (10 mg/ml) for 16 h for ICAM-1. As detected by cell-ELISA, ICAM-1 was expressed at low levels on unstimulated endothelial cells and was induced almost three fold by stimulation with TNF-a. The cinnamates, thiocinnamates and thionocinnamates treatment inhibited the TNF-a expression of ICAM-1 at various concentrations. The IC50 of each compound was calculated separately (Tables 1-3). It was found that the compound, ethyl 3,4,5-trimethoxythionocinnamate (ETMTC) most potently inhibited the TNF-α induced expression of ICAM-1.

ETMTC inhibits TNF-α induced expression of VCAM-1 and E-selectin:
The effect of ETMTC was examined on TNF-a induced expression of other cell adhesion molecules like VCAM-1 and E-selectin. Human endothelial cells were incubated with or without the thionocinnamate 29 at various concentrations for 2 h prior to induction with TNF-a (10 mg/ml) for 16 h for VCAM-1 and 4 h for E-selectin. As detected by cell-ELISA, ICAM-1 was expressed at low levels on unstimulated endothelial cells and was induced almost three fold by stimulation with TNF-a (Fig. 1). Interestingly, treatment of cells with ETMTC led to a drastic inhibition in TNF-a induced expression of ICAM-1 in concentration dependent manner (Fig. 1). The inhibition of TNF-a induced expression of ICAM-1 was approximately 90 %, whereas VCAM-1 and E-selectin were inhibited by more than 95 % (Fig. 1). The inhibition pattern by ETMTC remains unchanged if HUVECs were stimulated with LPS instead of TNF-α.
The inhibitory activity of ETMTC on ICAM-1, VCAM-1 and E-selectin expression was further confirmed by flow cytometry (Fig. 2A-C). The unstimulated cells expressed low levels of ICAM-1, VCAM-1 and E-selectin. Upon stimulation with TNF-a a substantial increase (5-6 folds) in the expression of all these three molecules was observed (Fig 2A-C). Pre-treatment of endothelial cells with ETMTC (20 mg/ml) inhibited TNF-a induced expression of ICAM-1, VCAM-1 and E-selectin, significantly >95 % (Fig 2A, B, C). Thus, ETMTC inhibits the induced expression of cell adhesion molecules as measured using cell-ELISA and confirmed by flow cytometry.
Reversible and time dependent effect of ETMTC
To study whether ETMTC causes any permanent change in the endothelial cells or not, endothelial cells were pre-incubated with ETMTC (20 mg/ml) for varying time periods ranging from 2 to 6 h, washed and allowed to recover for 1 h, followed by induction with TNF-a (10 mg/ml) for 16 h. As detected

by cell-ELISA, the effect of ETMTC was found to be reversible. Endothelial cells were found to be fully responding to TNF-a. This indicate that ETMTC not causing any damage to endothelial cells upon treatment with ETMTC. Furthermore, we have seen that ICAM-1 inhibition by ETMTC is time dependent. We found that only pre-treatment of cells with ETMTC inhibited the expression of ICAM-1 on endothelial cells whereas post-treatment had no significant effect (data not shown). This finding indicates that ETMTC interferes with some earlier steps of signalling cascade for inhibiting the TNF-a induced expression of cell adhesion molecules.
ETMTC inhibits neutrophils adhesion to endothelial monolayer:
The role of ICAM-1, VCAM-1 and E-selectin in the adhesion of neutrophils to endothelial monolayer is well established. To elucidate the functionality of inhibition of cell adhesion molecules by ETMTC, we studied the effect of ETMTC on the adhesion of neutrophils to endothelium. Endothelial cells were incubated with or without ETMTC at various concentrations for 2 h prior to induction with TNF-a (10 mg/ml) for 6 h. As detected by colorimetric assay, there was low adherence of neutrophils on unstimulated endothelial cells and was induced more than three-fold by stimulation with TNF-a (data not shown). Interestingly, ETMTC significantly inhibited the adhesion of neutrophils to endothelium in a concentration dependent manner and this inhibition was estimated approximately 90 % at concentration 20 mg/ml (Fig. 3).
The compounds of the present invention were examined against ICAM-1 inhibitory activity.
To examine the effect of side chain modification, various cinnamates, thiocinnamates and thionocinnamates were prepared. Different side chain compounds gave very different activity. Initial observation showed clear preference for ethyl group on the side chain. Lengthening or shortening the

chain length in naturally existing cinnamate resulted in a decrease in the activity. For example IC50 of ethyl 3',4',5' trimethoxycinnamate was found to be 25 whereas, methyl analog (shorter chain) ethyl y^S' trimethoxycinnamate having IC50 100 and longer chain analogue propylcinnamate (IC50 100). However, isopropyl 1 showed 80% inhibition at 65 mg/ml concentration. This is true not only for synthetic analog of ethyl trimethoxycinnmate but also true for dimethoxy 3-5 methoxy 6 and unsubstituted 7 and 8 analogues. In addition to this, dihydro analogs (propionate) having modest effect of side chain. Trimethoxy compounds 9 and 10 have nearly same activity and dimethoxy compounds 11 and 12 were almost same.
Table 1: ICAM-1 inhibitory activity Cinnamates 1-12
(Table Removed)

* Concentrations used where around 95 % cells are viable.
*-' These compounds did not reach up to 50 % inhibition even at maximum tolerable concentration.
The replacement of oxygen by sulfur was found to be more potent than the oxygen containing molecules (7). To validate this hypothesis further, we have synthesized sulfur containing cinnamates i.e. thiocinnamates and thionocinnamates. This was evident from Table 1. On comparing the activity of the following compounds 13 and 7, 13 and 17, 25 and 31,
29 and 32 &
30 and 44,
It was observed that compounds 7, 17, 31, 32 and 44 had higher IC50 than the compounds 13,13, 25, 29 and 30 respectively. However, dihydro analogs 39 and 42 were not consistent. This convincingly suggested that, replacement of oxygen by sulphur made our synthetic drug candidate more potent than

the naturally occurring candidate. However, same trend was observed for these compounds on modulation of side chain, as was found for analogs of naturally occurring cinnamate analogs.
Table 2: ICAM-1 inhibitory activity of thiocinnamates 13-28
(Table Removed)

* Concentrations used where around 95 % cells are viable.
'-' These compounds did not reach up to 50 % inhibition even at maximum tolerable concentration.
Table 3: ICAM-1 inhibitory activity of thionocinnamates 29-36
(Table Removed)
* Concentrations used where around 95 % cells are viable.
Compound no. 29, was the most active (IC50/ 10 ng/ml) among all the analogs. Activity reduced with a decrease in the number of methoxy groups on benzene ring (Table-1). This trend persisted in dihydro analogs, particularly the dihydro cinnamate analogs (propanoates) having lower activity than the unsaturated analogs (cinnamates).

The efficacy of thiono analog was found to be 200 times more than the natural molecule. Furthermore, when the activity of the compounds of the present invention was compared with well known compounds like aspirin, mesalamine and phenyl methimazole which inhibit the TNF-a induced expression of VCAM-1 at IC50 of 6000 uM, 16,000 µM and 500 µM, respectively (22-24), it was found that the compounds of the present invention are very promising as said compounds are working at very low concentration (IC5o 40 µM) as compared to these well known compounds. Similarly, diclofenac, N-acetylcysteine and pyrrolidone dithiocarbamate are most effective at concentrations of 750 µM, 100 uM and 1000 µM, respectively (25, 26). In comparison, the IC50 value of thiono analog (29) is around 40 uM. This concentration is comparatively lower if one considers the above examples of lead molecules or drugs that are in clinical use. Therefore, these results indicate that the compounds of the present invention are potentially effective and therefore, could be useful for further pharmaceutical studies.
Although the disclosure of system and method has been described in connection with the embodiment of the present disclosure illustrated in the examples, it is not limited thereto. It will be apparent to those skilled in the art that various substitutions, modifications and changes may be made thereto without departing from the scope and spirit of the disclosure.
These and other changes can be made to the embodiments in light of the above-detailed description. In general, in the following claims, the terms used should not be construed to limit the claims to the specific embodiments disclosed in the specification and the claims, but should be construed to include all possible embodiments along with the full scope of equivalents to which such claims are entitled. Accordingly, the claims are not limited by the disclosure.

We Claim:
1. Thionated cinnamate compound of formula I:
(Formula Removed)
wherein
R3R5
M represents or orc=c;
X represents 0 or S;
Y represents OR7, SR7 or N R8R9;
R1-R6 each independently represents H, (CH2)nOH, (CH2)nSH,
(CH2)nhalogen, alkyl, (CH2)naryl, (CH2)nOalkyl, (CH2)nSalkyl,
(CH2)nCOalkyl, (CH2)nCSalkyl, (CH2)nCOOH, (CH2)nCOOalkyl,
(CH2)nCOOaryl, (CH2)nCOSalkyl, (CH2)nCSOalkyl, (CH2)nCOSaryl,
(CH2)nCSOaryl, (CH2)nNH2/ (CH2)nNHalkyl, (CH2)nN(alkyl)2,
(CH2)nNHacyl, (CH2)nCN, (CH2)nNO2;
R7 can be H, alkyl, (CH2)naryl;
R8, R9 each independently represents H, alkyl, (CH2)naryl;
R10-R14 each independently represents H, alkyl, aryl, Oalkyl, Oaryl,
OCO alkyl, OCOaryl, amino or substituted amino, (CH2)nhalogen,
(CH2)naryl, (CH2)nOH, (CH2)nSH, (CH2)nOalkyl, (CH2)nSalkyl,
(CH2)nOaryl/ (CH2)nSaryl, (CH2)nNH2, (CH2)nNHalkyl, (CH2)nN(alkyl)2,
(CH2)nNHacyl, (CH2)nCN, (CH2)nNO2, (CH2)nCOOH, (CH2)nCSOH,
(CH2)nCOSH, (CH2)nCOOalkyl, (CH2)nCOOaryl, (CH2)nCSOalkyl,
(CH2)nCOSaryl, (CH2)nCOSalkyl, (CH2)nCSOaryl, (CH2)nCONH2,

(CH2)nCONHalkyl/ (CH2)nCON(alkyl)2, R7-C-Z-