The title compound, C(19)H(21)N(3)O(3)S, was synthesized via the aza-Wittig reaction of functionalized imino-phospho-rane with phenyl isocyanate under mild conditions. In the mol-ecule, the fused thienopyrimidine ring system is essentially planar, with a maximum deviation of 0.072 (2) Å, and makes a dihedral angle of 60.11 (9)° with the phenyl ring. An intra-molecular C-H⋯O hydrogen bond is pre...

Krystyna Lesiak and Wojciech J. Stec Polish Academy of Sciences, Centre of Molecular and Macromolecular Studies, 90-362 Lodz, Boczna 5, Poland Z. Naturforsch. 33b, 782-785 (1978); received March 28, 1978 1,3,2-Oxazaphospholidines, (—)Ephedrine, Thioanilides, Thioesters, Stereochemistry Both isomers of 2-anilido-3,4-dimethyl-5-phenyl-l,3,2-oxazaphospholidine-2-thiones (2 a and 2 b) derived from ...

The first total synthesis of the cytotoxic marine macrolide enigmazole A has been completed in 22 steps (longest linear sequence). The sensitive, densely functionalized 2,4-disubstituted oxazole fragment was constructed using an efficient Negishi-type coupling of an oxazol-2-ylzinc reagent formed directly from the parent ethyl 2-iodooxazole-4-carboxylate by zinc insertion. Other key steps inclu...

Three novel pyrazolo[3,4-b]pyridines were synthesized via the cyclization of 5-amino-1-phenylpyrazole with corresponding unsaturated ketone in catalytic presence ZrCl4. The ketones afforded by modifying a stabilized ylide facilitated Wittig reaction fairly high yields. compounds exhibited exciting photophysical properties dimethylamine phenyl-bearing pyrazolopyridine showing exceptionally large...

Coumarin and its derivatives represent one of the most active curriculums compound possessing a broad spectrum biological activity along with other applications such as insecticide fragrance. There are various methodologies developed for synthesis coumarins. Classical routes to coumarins include Pechmann condensation, Knoevenagel Perkin reaction, Wittig condensation reactions. Researchers have ...

Abstract Synthesis of assumed natural (12R,13S)-enantiomers pyriculariol (1) and dihydropyriculariol (2), phytotoxins isolated from rice blast disease fungus, Pyricularia oryzae, was achieved using Wittig reaction or microwave-assisted Stille coupling as the key step. The synthesis revealed that 1 2 are racemates. Foliar application test on a leaf indicated both salicylaldehyde core side chain ...

A fast and efficient protocol for the synthesis of N,N'-disubstituted urea derivatives from alkyl halides and primary or secondary amines has been developed. The synthetic pathway combines nucleophilic substitutions and a Staudinger-aza-Wittig reaction in the presence of polymer-bound diphenylphosphine under 14 bar of CO2 pressure and has been performed in a one-pot two-step process. The protoc...