Several biotinyl estradiol derivatives have been prepared by coupling estradiol 7 alpha-carboxylic acid to biotin via different linear linkers. All these compounds exhibit a high affinity for the estrogen receptor as determined by competitive binding assays against [3H]estradiol. These compounds also displaced the dye 4-hydroxyazobenzene-2'-carboxylic acid from the biotin-binding sites of avidi...

Cephalosporin acylase (EC 3.5.1.11) obtained from Kluyvera citrophila ATCC 21285 was found to catalyze synthesis of 7-[2-(2-thienyl)acetamido]-3-trifluoromethyl-3-cephem-4-carboxylic acid from methyl thienylacetate and dl-7-amino-3-trifluoromethyl-3-cephem-4-carboxylic acid. The enzymatically-synthesized compound showed [alpha]25 D + 42.7 degrees (c 0.058, MeOH) and its biological activity was ...

Thermal analysis of acrylonitrile/acrylic acid P(AN/AA) copolymer films containing 5%, 10% and 20% acrylic acid dendrigrafted with citric acid (CA) is examined using differential scanning calorimetry (DSC) with various heating rates, thermogravimetry (TGA) and derivative thermogravimetric analysis (DTG). Also, the effect of carboxylic acid on thermal stabilization of the P(AN/AA) copolymers, wh...

7-(D-5-Amino-5-carboxy-valeramido)-3-(acetylhydrazido)-8-oxo-5-thio-1-azabicyclo [4,2,0]-oct2-ene-2-carboxylic acid (1). 7-(D-5-Amino-5-carboxy-valeramido)-3-(substitutedarylacetylhydrazido)8-oxo-5-thio-1-azabicyclo[4,2,0]-oct-2-ene-2-carboxylic acid.(2-5). 7-(D-5Amino-5carboxyvaleramido)3(2'substituted aryl-3'-chloro-4'-oxo-azetidin-1'-yl)-acetylamino]-8-oxo-5-thio-1azabicyclo[4,2,0]-oct-2-ene...

barium salts of dibenzylidene cystines 8a-c were obtained from the reaction of lcystine with benzaldehyde or its derivatives in the presence of barium hydroxide. their reduction with zinc and hydrochloric acid in methanol yielded the narylmethylcysteines ?9a-c?. these can, in turn, be converted by esterification into the methyl esters ?10 a-c. ?reaction of n, n'-carbonyl diimidazole (im co...

Condensation of the corresponding chlorides of some substituted pyrazine-2-carboxylic acids (pyrazine-2-carboxylic acid, 6-chloropyrazine-2-carboxylic acid, 5-tert-butylpyrazine-2-carboxylic acid or 5-tert-butyl-6-chloropyrazine-2-carboxylic acid) with various ring-substituted aminothiazoles or anilines yielded a series of amides. The syntheses, analytical and spectroscopic data of thirty newly...

Abstract Coumarin and its nitrogen analogue 1-aza coumarin are a class of lactones lactams, respectively, which indispensable heterocyclic units to both chemists biochemists. 1-Aza derivatives, ultimately metabolize as the corresponding 8-hydroxy coumarins in biological system therefore found be very good anti-inflammatory, anti-cancer, analgesic agents. A series hybrid substituted azacoumarin-...

The purpose of this study was to evaluate the involvement of endothelin (ET)(B) receptor-mediated action in the sex differences in balloon injury-induced neointimal formation using the spotting-lethal rat, which carries a naturally occurring deletion in its ET(B) receptor gene. Male and female ET(B)-deficient and wild-type rats underwent balloon injury of the carotid artery. In the wild-type ra...

with urease. A third minor metabolite was present in urine collected after intraperitoneal administration but remains unidentified. The quantitative distribution of pterin-dcarboxylic acid and urea in the 0-24 h urine samples is shown in Table 1. Fukushima & Nixon (1980) reported the degradation of [2-14C]pterin-6-carboxylic acid to 14C02 by the gut microorganisms of the rat. It is possible tha...