Organotin(IV) tryptophanylglycinates: potential non-steroidal antiinflammatory agents; crystal structure of dibutyltin(IV) tryptophanylglycinate

✍ Scribed by Mala Nath; Hitendra Singh; Parvinder Kumar; Ashok Kumar; Xueqing Song; George Eng

• Book ID: 101571767
• Publisher: John Wiley and Sons
• Year: 2009
• Tongue: English
• Weight: 293 KB
• Volume: 23
• Category: Article
• ISSN: 0268-2605
• DOI: 10.1002/aoc.1514

✦ Synopsis

Abstract

Diorganotin(IV) derivatives of tryptophanylglycine (H~2~Trp–Gly) with general formula R~2~Sn(Trp–Gly), where R = Me, n‐Bu, Ph and n‐Oct, and triorganotin(IV) derivatives R′~3~ Sn(HTrp–Gly) where R′ = Me, n‐Bu and Ph, have been synthesized and structurally characterized in the ‘solid state as well as in solution on the basis of various spectroscopic techniques, viz. FT‐IR, multinuclear ^1^H, ^13^C and ^119^Sn NMR, ^119^Sn Mössbauer and single crystal X‐ray diffraction. These investigations suggest that tryptophanylglycine in R~2~Sn(Trp–Gly) acts as dianionic tridentate coordinating through carboxylate oxygen [C(O)O^−^], amino nitrogen (NH~2~) and N^−^~peptide~, while in the case of R′~3~ Sn(HTrp–Gly), the ligand acts as monoanionic bidentate coordinating through C(O)O^−^ and NH~2~. This is further confirmed by the single‐crystal X‐ray structure of n‐Bu~2~Sn(Trp–Gly) which shows that two butyl groups and peptide nitrogen (N^−^~peptide~) are in the equatorial positions, while the two axial positions are occupied by the carboxylic oxygen [C(O)O^−^] and the amino nitrogen (NH~2~) atom from the same ligand molecule in the distorted trigonal–bipyramidal geometry around tin. The anti‐inflammatory (using the carrageenan‐induced paw edema bioassay in rats), cardiovascular activities and acute toxicity (LD~50~) of some of these compounds have been examined. All of the studied R~2~Sn(Trp–Gly) and Ph~3~Sn(HTrp–Gly) exhibit very high anti‐inflammatory activities comparable to that of phenylbutazone along with high safety margin (LD~50~ > 400 mg kg^−1^) with no side effects on the cardiovascular system. Copyright © 2009 John Wiley & Sons, Ltd.