𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Oxidative ring-opening of rel-(2R,3R,5S)-5-aryl-2-benzoylamino-6,7-bis(methoxycarbonyl)-2,3-dihydro-1-oxo-3-phenyl-1H,5H-pyrazolo[1,2-a]-pyrazoles. Synthesis of rel-(2R,3R)-3-phenyl-3-[5-aryl-3,4-bis(methoxycarbonyl)pyrazolyl-1]alanine esters

✍ Scribed by Andrej Prešeren; Jurij Svete; Branko Stanovnik

Publisher
Journal of Heterocyclic Chemistry
Year
1999
Tongue
English
Weight
157 KB
Volume
36
Category
Article
ISSN
0022-152X

No coin nor oath required. For personal study only.

✦ Synopsis

Abstract

rel‐(2__R__,3__R__)‐N‐Benzoylamino‐6,7‐bis(methoxycarbonyl)‐2,3‐dihydro‐1‐oxo‐1__H__,5__H__‐pyrazolot[1,2‐a]‐pyrazoles 5, accesible by cycloaddition of dimethyl acetylenedicarboxylate (3) to (1Z)‐rel‐(4__R__,5__R__)‐1‐aryl‐methylidene‐4‐benzoylamino‐5‐phenyl‐3‐pyrazolidinone‐1‐azomethine imines 4, undergo oxidative ring cleavage with methanolic bromine giving rel‐(2__R__,3__R__)‐N‐benzoyl‐3‐phenyl‐3‐[5‐aryl‐3,4‐bis(methoxy‐carbonyl)pyrazolyl‐1]alanine methyl esters 6 as products.

📜 SIMILAR VOLUMES

The synthesis of pyrazolo[1,2-a]pyrazole
The synthesis of pyrazolo[1,2-a]pyrazoles. Regio- and stereo-selective 1,3-dipolar cycloadditions of (1Z)-rel-(4R,5R)-1-arylmethylene-4-benzoylamino-5-phenyl-3-pyrazolidinon-1 -azomethinimines
✍ Jurij Svete; Andrej Prešeren; Branko Stanovnik; Ljubo Golič; Simona Golič-Grdado 📂 Article 📅 1997 🏛 Journal of Heterocyclic Chemistry 🌐 English ⚖ 420 KB

## Abstract Reaction of __rel__‐(4__R__,5__R__)‐4‐benzoylamino‐5‐phenyl‐3‐pyrazolidinone (4) with aromatic aldehydes 5a‐f gave the corresponding (1__Z__)‐__rel__‐(4__R__,5__R__)‐1‐arylmethylene‐4‐benzoylamino‐5‐phenyl‐3‐pyrazolidinon‐1‐azomethinimines 6a‐f. 1,3‐Dipolar cycloadditions of azomethinim