Regioselective Synthesis of New 2-(E)-Cyano(thiazolidin-2-ylidene)thiazoles

Mehdi Bakavoli,Mohammad Rahimizadeh,Reza Takjoo,Hamid Beyzaie,Hossein Eshghi

doi:10.3390/molecules14114849

Abstract

Cyclocondensation of 2-[bis(methylthio)methylene]malononitrile (1) and cysteamine (2) afforded 2-(thiazolidin-2-ylidene)malononitrile (3). This compound on treatment with NaSH gave the corresponding thioamide derivative 4a in a regioselective manner on the basis of its single crystal X-ray diffraction analysis. Reaction of this compound with several α-bromocarbonyl compounds gave new 2-(E)-cyano(thiazolidin-2-ylidene)thiazoles 5a-g.

Highlights

Thiazole is an important scaffold in heterocyclic chemistry and 1,3-thiazole ring is present in many pharmacologically active substances [1]
One procedure involves nitriles which can be converted to thioamides through treatment with elemental sulfur, S8 [14,15], gaseous hydrogen sulfide in the presence of anion exchange resin
Our interest in the synthesis of heterocyclic compounds of biologically importance has encouraged us to study the synthesis of some new functionalized thiazoles. In this context we wish to report on the reactions and single crystal X-ray diffraction analysis of a newly synthesized thioamide which on treatment with various α-bromocarbonyl compounds afforded some new 2-(E)-cyano(thiazolidin-2ylidene)thiazoles

Summary

Introduction

Thiazole is an important scaffold in heterocyclic chemistry and 1,3-thiazole ring is present in many pharmacologically active substances [1]. In this context we wish to report on the reactions and single crystal X-ray diffraction analysis of a newly synthesized thioamide which on treatment with various α-bromocarbonyl compounds afforded some new 2-(E)-cyano(thiazolidin-2ylidene)thiazoles.

Results

Conclusion