by T ADASHT HrRAKo, National Leprosarium, Tama Zenshoen. The treatment of leprosy has gradually improved since n umerous anti-leprosy d rugs have been introduced not only sulphone compounds such as D.D.S. but also other types of preparations, thiourea derivatives, and antibiotics. Until ETISUL was recently reported to be effective for tuberculosis and also leprosy, there were no effective drugs...

A series of thiourea and guanidinium derivatives have been prepared and their ability to bind a carboxylate group has been investigated. Guanidinium 33, featuring two additional amides and a pyridine moiety, proved to be the most potent carboxylate binding site and was able to bind acetate in aqueous solvent systems (K(ass) = 480 M(-1) in 30% H(2)O-DMSO). The pyridine moiety is critical to obta...

An enantioselective α-oxyamination of unprotected 3-substituted oxindoles with nitrosobenzene catalyzed by tertiary amine-thiourea bifunctional organocatalysts has been developed and affords the corresponding 3-amino-2-oxindole derivatives in good yields and with moderate to excellent enantioselectivities (up to > 99.9 : 0.1 er when the product is isolated by direct filtration from the reaction...

An efficient and green method has been developed for the synthesis of new substituted Hantzsch thiazole derivatives in 79%-90% yield, via the one-pot multi-component procedure, by the reaction of 3-(bromoacetyl)-4-hydroxy-6-methyl-2H-pyran-2-one, thiourea and substituted benzaldehydes in the presence of silica supported tungstosilisic acid, as a reusable catalyst, under conventional heating or ...

An efficient synthesis of highly functionalized chiral β-amino ester derivatives containing benzothiophene and benzothiazole moieties is developed by a Mannich-type reaction using a cinchona alkaloid-derived thiourea catalyst. The desired products were obtained in good yields and high enantioselectivities (~86% yield, >99% ee) using to the optimized reaction conditions. The synthesized compound...

The present paper describes studies on the synthesis of the antiepileptic drug phenytoin, and of structurally related derivatives. First, the influence of the solvent has been investigated in the microwave-assisted synthesis of the drug, resulting in a yield improvement and a cleaner reaction. Second, a two-step reaction is described to synthesize selectively and in high yields phenytoin. The f...

The reaction of the tetrahydrobenzo[b]thiophene derivatives 1a,b with benzoylisothiocyanate (2) afforded the thiourea derivatives 3a,b. Cyclization of the latter products gave the annulated products 4a,b. Compounds 3a,b reacted with either hydrazine hydrate (5a) or phenyl hydrazine (5b) afforded compounds 7a-d which underwent cyclization for compounds 7a,c afforded compound 9. On the other hand...

We prepared and characterized a grinding-induced equimolar complex of thiourea with ethenzamide. When thiourea and ethenzamide were co-ground at a molar ratio of 3 : 1, new powder X-ray diffraction (PXRD) peaks were observed in addition to PXRD peaks of thiourea crystals. The optimum stoichiometry of the new structure was confirmed as 1 : 1 mol/mol. Effect of grinding time on the thiourea-ethen...

Oxindoles and their indoline derivatives are common structural motifs found in a wide array of natural and biologically active molecules. Most catalytic methods for the asymmetric syntheses of these compounds rely heavily on the use of transition-metal catalysts. In contrast, alternative catalytic procedures involving organocatalysis are scarce. Herein we disclose a conceptually novel organocat...