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(15.XI. 95)Ten new a -diazo$-oxoaldehydes were condensed with aniline, ammonia, hydroxylamine, and semicarbazide to yield new 4-acyl-(l-substituted)-l H-l,2,3-triazoles in moderate-to-good yields. The method is simple and regiospecific. The latter feature makes this method superior to the widely used acylacetyiene + azide approach.

Triazole derivativesTriazole derivatives R 0280 Synthesis and Investigation of Tuberculosis Inhibition Activities of Some 1,2,3-Triazole Derivatives. -Condensation of α-diazo-β-oxoaldehydes (I) with different amines (II) affords the title compounds in good yields. -(DABAK*, K.; SEZER, O.; AKAR, A.; ANAC, O.; Eur. J. Med. Chem. 38 (2003) 2, 215-218; Dep. Chem., Fac. Sci., Tech. Univ. Istanbul, TR-80626 Maslak, Istanbul, Turk.; Eng.) -M. Paetzel 24-107

In this study, synthesis of some new 1,2,3-triazole derived potential scaffold type peptidomimetics are described.

Diazomethyl ketones (2-diazoethanones) were reacted with the Vilsmeier reagent ((chloromethylidene)dimethylammonium chloride) to yield a-diazo-p-oxoaldehydes and chloromethyl ketones. 2',4-Dimethoxy-udiazoacetophenone gave 2-chloro-1-(2,4-dimethoxyphenyl)-3-(dimethylamino)prop-2-en-l-one ( 5 ) in addition to the expected products. Phenyldiazomethanes gave the corresponding benzyl chlorides but not the (pheny1)diazoacetaldehydes even at temperatures as low as -60". The diazo-transfer reactions of phenylacetaldehydes and 2-azido-1 -ethylpyridjn-l -ium tetrafluomborate also did not yield the expected(pheny1)diazoacetaldehydes.Introduction. -a-Diazo-p-oxoaldehydes (1) are valuable synthetic tools with their interesting chemical behavior. In the first part of this series, we reported a fairly general synthetic method for these compounds using a novel diazo-transfer reaction (Scheme 1) [2]. On the other hand, the first report on their synthesis came from Stojanovic and Arnold almost thirty years ago (Scheme 2) [3], seven years after Bosshard and Zollinger had shown in this journal that the Vilsmeier reactions are due to the intermediate formation of (chloromethy1idene)dimethylammonium chloride from dimethylformamide and thionyl chloride (or sulfuryl chloride) [4]. Although the method was low yielding, it was applied to the syntheses of etyhl a-diazo-cr-formylacetate and 2-diazo-3-oxo-3-phenylpropanol which were the only successful examples. Since it had no alternatives, it has been used so far for the synthesis of those compounds. In his papers, Arnold reported that similar formylations of diazoacetone [ 3 ] , diazoacetaldehyde [5], and phenyldiazomethane [3] had not given any identifiable products. Our method was also not successful in certain cases : p-oxoaldehydes (2) possessing electron-releasing R groups such as 2,4-dimethoxyphenyl, t-Bu, and fury1 have a high tendency to undergo deforinylation during the diazo transfer reaction, thus yielding diazomethyl ketones (3) to a higher extent than

A new synthetic method for the preparation of the cholesterol-lowering drug simvastatin from the naturally occurring lovastatin is reported. The synthesis employs first the protection of the OH group of lovastatin (1) and then the protection of the lactone CO group to prevent enolization via conversion to the orthoesters 4a and 4b. Alkylation of the 2-methylbutyrate side chain is then successfully achieved. Removal of the protecting groups affords antihypercholesterolemic agent simvastatin (2).Introduction. ± Simvastatin (2), like other statins (lovastatin (1), pravastatin, mevastatin, atorvastatin, fluvastatin, cervastatin, etc., derivatives and analogs thereof) is a (hydroxymethyl)glutaryl coenzyme A reductase (HMG-CoA reductase) inhibitor and is used as an antihypercholesterolemic agent [1 ± 5].

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