Development of metronidazole-resistant lines of Blastocystis sp.

Metronidazole (MTR) is frequently used for the treatment of Blastocystis infections, but with variable effectiveness, and often with treatment failures as a possible result of drug resistance. We have developed two Blastocystis MTR-resistant (MTR(R)) subtype 4 WR1 lines (WR1-M4 and WR1-M5), with variable susceptibility to a panel of anti-protozoal agents including various 5-nitroimidazoles, nitazoxanide and furazolidone. WR1-M4 and WR1-M5 were developed and assessed over an 18-month period and displayed persistent MTR resistance, being more than 2.

High functionalization of 5-nitro-1H-imidazole derivatives: the TDAE approach.

We report herein the synthesis of substituted 2-[4-(1,2-dimethyl-5-nitro-1H-imidazol-4-yl)phenyl]-1-arylethanols, ethyl 3-[4-(1,2-dimethyl-5-nitro-1H-imidazol-4-yl)-phenyl]-2-hydroxypropanoate and 2-[4-(1,2-dimethyl-5-nitro-1H-imidazol-4-yl)benzyl]-2-hydroxy-acenaphthylen-1(2H)-one from the reactions of 4-[4-(chloromethyl)phenyl]-1,2-dimethyl-5-nitro-1H-imidazole with various aromatic carbonyl and a-carbonyl ester derivatives using tetrakis(dimethylamino)ethylene (TDAE) methodology.

TDAE-assisted synthesis of new imidazo[2,1-b]thiazole derivatives as anti-infectious agents.

A series of new imidazo[2,1-b]thiazoles was prepared in moderate to good yields in a four step synthesis using the TDAE methodology from 6-chloromethyl-5-nitroimidazo[2,1-b]thiazole and keto esters, ketomalonates and ketolactams. All compounds were tested for their antibacterial and antifungal activities against four bacterial strains (two Gram positive and two Gram negative ones) and four yeasts. Among these synthesized 5-nitroimidazo[2,1-b]thiazoles, the compounds 1 and 6 showed potent antimicrobial activities against all candida strains and compound 3e showed an interesting antifungal potential against Candida tropicalis.