different procedures for the syntheses of the title compounds were investigated. the best method for the preparation of the title compounds were the reaction of the readily available 2-formyl-1-methyl-5-nitroimidazole2- substituted-4-formylthiazoles with alkyl acetoacetate and alkyl aminocrotonate in boiling alcohol.

Reaction of substituted-aniline (8) with ethyl (l-methyl-5-nitroimidazole-2- carbonyl) acetate (9) gave 4-hydroxy-2-(l-methyl-5-nitro-2-imidazolyl)- substituted-quinolines (lo), which were converted to compound 11 with phosphorus oxychloride. Substituted-2-(l-methyl-5-nitro-2-imidazo1yl)-4.- methyl-(or phenyl-) quinolines (14) were prepared through the reaction of 2- acetyl-5-nitro-1-methy...

Colchicine, the major alkaloid of the meadow saffron, is one of the most prominent natural products and, like other tubulin-binding natural products (e.g. taxol and the epothilones), exhibits great pharmaceutical potential. The first syntheses in the late 1950s were milestones in natural product synthesis. But even today this structurally supposedly simple molecule poses a challenge to syntheti...

Here we report the synthesis of all four stereoisomers of mefloquine. Mefloquine (Lariam) is an important anti-malaria drug that is applied as a racemate of the erythro form. However, the (-)-isomer induces psychosis, while the (+)-enantiomer does not have this undesired side effect. There are six syntheses of which five lead to the wrong enantiomer without the authors of these syntheses noting...

The first enantioselective total syntheses of the proposed structures of the natural product prevezol B are reported. The reported syntheses complement the previously-reported syntheses of the proposed structures of prevezol C, a stereoisomer of prevezol B. It was previously shown that the structure of the naturally occurring prevezol C had been incorrectly assigned. This work has led us to con...

Literature on the combination of qualitative and quantitative research components at the primary empirical study level has recently accumulated exponentially. However, this combination is only rarely discussed and applied at the research synthesis level. The purpose of this paper is to explore the possible contribution of mixed methods research to the integration of qualitative and quantitative...

Aldolase antibody 38C2-catalyzed resolutions of tertiary aldols were studied. Tertiary aldols proved to be very good substrates for antibody catalyzed retro-aldol reactions. The catalytic proficiency, (kcat/KM)/ kuncat, of the antibody for these reactions was on the order of 1010 M-1. A fluorogenic tertiary aldol allowed for the quantitative study of enantiomeric excess as a function of reactio...

The coordination of the syntheses of the several cellular lipid classes with one another and with cell cycle control were investigated in proliferating L6 myoblasts and fibroblasts (WI-38 and CEF). Cells cultured in lipid-depleted medium containing one of two inhibitors of hydroxymethylglutaryl-CoA reductase, 25-hydroxycholesterol or compactin, display a rapid, dose-dependent inhibition of chol...

The spread of professional microwave (MW) reactors in the last 25 years brought about a revolutionary change in synthetic organic chemistry. This methodology has also had a positive inpact on organophosphorus chemistry enhancing reluctant reactions, or just making the reactions more efficient in respect of rate, selectivity and yield. In special cases, MW irradiation may substitute catalyst, or...

The enantioselective total syntheses of (-)(E)ybisabolene-8,9-epoxide, (+) (2S,6R)-2-bromo-13-chamigrene, and (+)-chamigrene, important intermediates in the biosynthesis of natural sesquiterpenoids isolated from algae of the genus Laurencia, are described. The compounds are synthesized with regio ñd stereocontrol by using simple forms of bridged intermediates. This represents a general strategy...