Diketopyrrolopyrroles are N-alkylated under mild conditions using secondary aliphatic and benzyl type alcohols.

Aim. The purpose of the present study was to develop a method for fixation ‘fixed’ conformation estimation impact calix[4]arene structure on efficacy its anticoagulant activity. This achieved by substitution lower rim C-145 analogue. Methods.Calix[4]arene C-145F (compound 6) obtained in 4 steps starting with Duff reaction. Calix[4]arene methylene-bis-phosphonic ester 3 prepared via addition dii...

Abstract (R)-Tenofovir phenyl ester ((R)-1) and (R)-tenofovir diphenyl ((R)-2) are key intermediates for the practical synthesis of tenofovir alafenamide fumarate, which is a mainstay antiretroviral treatment chronic hepatitis B HIV-1 infections. This article deals with chiral analysis (R)-1 (R)-2 against their respective optical impurity (S)-tenofovir ((S)-1) ((S)-2) using polysaccharide-coate...

A formal synthesis of the antiviral drug (-)-oseltamivir (Tamiflu) has been accomplished starting from m-anisic acid via a dissolving metal or electrochemical Birch reduction. The correct absolute stereochemistry is efficiently set through enzyme-catalyzed carbonyl reduction on resultant racemic α,β-unsaturated ketone. screen broad ketoreductase (KRED) library identified several that deliver de...

Treatment of triphenylphosphine (Ph(3)P) with an excess of diisopropyl azodicarboxylate at 0-25 °C resulted in the formation of a symmetrical tetraalkyl tetrazetidinetetracarboxylate radical cation, containing the elusive cyclic N(4) ring system. Electron paramagnetic resonance (EPR) spectroscopy revealed a 9-line spectrum, with hyperfine coupling constants indicative of four almost magneticall...