We studied the kinetics of the reaction between cholesterol and sulfuric acid in acetic acid-acetic anhydride medium. Results have been used to establish near-optimal conditions for the fast kinetic determination of cholesterol in serum. The reaction rate measured during the first 20 s of the reaction is proportional to cholesterol concentration. There is good agreement (<2% deviation) between ...

5-Aryl-7-hydrazino-2-phenylpyrazolo[1,5-c]pyrimidines 1 were used as precursors for the preparation of a new series of 5-aryl-8-phenylpyrazolo[1,5-c]-1,2,4- triazolo[4,3-a]pyrimidines 2. The reactions of 2 with certain electrophilic reagents gave the respective 6-substituted derivatives 3-5 rather than the 7-isomeric products. Formylation of the key compounds 1 with ethyl formate yielded the fo...

In this study, Cu-Ni-Fe-Cr layered double hydroxide (LDH) immobilized on silica magnetite (Fe3O4@SiO2@Cu-Ni-Fe-Cr LDH) was investigated towards ring opening of diverse epoxides with acetic anhydride to afford vic-diacetates within 15–40 min in high yields. Reusability the nano-LDH also studied for 6 consecutive cycles without significant loss catalytic activity.

LEERS AND Lowa (1) HAVE PUBLISHED a method for the estimation of cholesterol on a micro scale in animal tissue by fluorometry involving the reaction of extracted cholesterol dissolved in trichloroethane with acetic anhydride and sulfuric acid. The present paper describes a simple and tested use of this reaction for the estimation of total cholesterol in 0.02 ml. of serum after extraction by a s...

During modification of protein amino groups with carboxylic acid anhydrides, these reagents cause a fall in pH, which can be prevented by addition of base. Although unmodified nucleosomal particles are not affected by the local transient changes in pH induced by the base (NaOH) added to prevent a fall in pH during modification, the nucleosomal particles modified by acetic anhydride are dissocia...

An efficient synthesis of 4-arylcoumarins has been accomplished via Kostanecki reactions of 2-hydroxybenzophenones with acetic anhydride employing DBU at ambient temperature. Using the same strategy, several 2-acyloxybenzophenone derivatives were readily converted to 3,4-difunctionalized coumarins. This protocol offers a notable improvement in reaction conditions for coumarin synthesis and take...

2-Alkyl-1-alkylthioisoquinolinium salts were readily prepared from 2-alkyl-1(2H)-isoquinolones via 2-alkyl1(2H)-thioisoquinolones in two steps. Under mild conditions, the reaction of 2-alkyl-1-alkylthioisoquinolinium salts with active methylene compounds in the presence of sodium hydride afforded 2-alkyl-1-(substituted methylene)iso-quinolines in good yields. Pyrrolo[2,1-a]isoquinolines were sy...

A simple, sensitive, rapid, reproducible, economical and easily accessible method for the determination of tinidazole tablets is described. From the experiment carried out there is the need for recrystallisation of tinidazole tablet before it is analysized. Ultraviolet (UV) absorption analysis corresponds to the result obtained with non-aqueous titration. And the best solvent to be use for non-...

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.