Synthesis and chemical properties of 1,2-dihydropyrrolizines (review)

Oxidation of heterocyclic compounds by manganese dioxide (Review)*

“…In pyrrolizidine 55 only the substituted ring is dehydrogenated, and the ester group is retained in the product 56 [58]. Dehydrogenation with MnO 2 was also realized successfully in five-membered heterocycles with two heteroatoms: The dihydro derivatives of pyrazoles [59,60], imidazoles [61], isoxazoles [62], and thiazoles [63,64] and also tetrahydrothiazoles [63][64][65][66].…”

(E)-2-(2-Furylmethylidene)-2,3-dihydro-1H-pyrrolizin-1-one

“…For general background to synthetic dihydropyrrolizines and for the biological activity of related structures, see: Meinwald & Meinwald (1965); Skvortsov & Astakhova (1992). For the preparation of the starting material, see: Clemo & Ramage (1931); Braunholtz et al (1962).…”

“…The most important of these, Ketorolac, is a non steroid analgesic. Depending on their structure, derivatives of 2,3-dihydropyrrolizine have shown merit as analgesics, anti-inflammatory agents, myorelaxants, inhibitors of thrombocyte aggregation, fibrinolytics, temperature-lowering substances and drugs for the treatment of glaucoma and conjunctivitis (Skvortsov & Astakhova, 1992).…”

2,3-Dihydro-1H-pyrrolizin-1-one

“…For general background to 2,3-dihydropyrrolizine derivatives and their biological activity, see: Skvortsov & Astakhova (1992). For the preparation, see: Braunholtz et al (1962); Clemo & Ramage (1931).…”

“…The most important of these, Ketorolac, is a non steroid analgesic. Depending on their structure, derivatives of 2,3-dihydropyrrolizine have shown merit as analgesics, anti-inflammatory agents, myorelaxants, inhibitors of thrombocyte aggregation, fibrinolytics, temperature-lowering substances and drugs for the treatment of glaucoma and conjunctivitis (Skvortsov et al, 1992).…”