A new facile route for synthesis of 3- (aryl) -8, 9- di (alkyl) thieno [3,2-e] [1,2,4] triazolo pyrimidines derivative from the same starting material, 2- amino - 4,5 -di (alkyl) thiophene-3- carboxamide, has been developed through heterocyclization of the corresponding arylidene-hydrazino -5,6 -di (alkyl) thieno [2,3-d] pyrimidine under refluxing condition with acetic anhydride followed by air...

a new facile route for synthesis of 3- (aryl) -8, 9- di (alkyl) thieno [3,2-e] [1,2,4] triazolo pyrimidines derivative from the same starting material, 2- amino - 4,5 -di (alkyl) thiophene-3- carboxamide, has been developed through heterocyclization of the corresponding arylidene-hydrazino -5,6 -di (alkyl) thieno [2,3-d] pyrimidine under refluxing condition with acetic anhydride followed by air...

An acetic anhydride pyridine mixture acetylates hydroxyl groups in tissue sections. The acetyl groups can be removed from tissue sections by weak alkali. Sections acetylated by acetic anhydride pyridine no longer produce aldehydes after oxidation by periodic acid. Acetylated sections subjected to weak alkali regain the ability to produce aldehydes after oxidation by periodic acid. Acetylation o...

In the presence of 1 mol% of a copper(II) catalyst and air, a readily available N-acetyl-N-thioacylguanidine undergoes a one-pot benzylic oxidation–oxidative heterocyclization sequence to give the 3-amino5-acyl-1,2,4-thiadiazole core of polycarpathiamines A (2) and B (3) and thus facilitating the first synthesis of both natural products. This methodology offers a straightforward alternative to ...

5-(1,2,3,4-Tetrahydroxybutyl)-2-methylfuran-3-carbohydrazide (2) was condensed with a variety of ketones to afford carbohydrazide derivatives 3-6. Acetylation of 3-5 afforded the acetyl derivatives 7-9, while periodate oxidation of 3-6 afforded the formyl derivatives 10-13. Acid catalyzed condensation of thiosemicarbazide or o-tolylthiosemicarbazide with the prepared aldehydes 10-12 gave thiose...

As shown in the previous paper, a metabolite of thiamine anhydride (TA) (I) was isolated as crystals melting at 172-173•‹ from the urine when TA was given parenterally to rats and it was assumed to be thiamine anhydride sulfoxide (TAO) (II) from its analytical data. It is known, however, that TA can be oxidized to TA sulfone (III) besides its sulfoxide by hydrogen peroxide according to the con ...

A novel and practical procedure for preparation of imides is described using chromium(VI) oxide to catalyze the oxidation of N-alkylamides with periodic acid in the presence of acetic anhydride in acetonitrile.

Acetylation reaction's product(s) o f 3-[L-threo-2,3,4-trihydroxy-1-(2-naphthylhydrazono)butyl]quinoxalin-2(lH)-one (2b) were found to be dependent on the reaction condition. While the tri-O-acetyl (3b) was isolated in high yield from 2 b under the action o f acetic anhydride/ pyridine mixture, compounds 4 b and 5 b as well as trace o f 3b were obtained when 2 b was heated in acetic anhydride. ...

The title compound, C(20)H(18)O(6), has been synthesized from 4-methoxy-phenyl 3-O-benzo-yloxy-α-l-rhamnopyran-oside by oxidation on treatment with pyridinium dichromate in the presence of acetic anhydride. In the mol-ecule, the pyran ring adopts an envelope conformation with the O atom at the flap position. Weak inter-molecular C-H⋯O hydrogen bonding is present in the crystal structure.