Organocatalytic Enantioselective Epoxidation of Some Aryl-Substituted Vinylidenebisphosphonate Esters: On the Way to Chiral Anti-Osteoporosis DrugsReport as inadecuate


Organocatalytic Enantioselective Epoxidation of Some Aryl-Substituted Vinylidenebisphosphonate Esters: On the Way to Chiral Anti-Osteoporosis Drugs


Organocatalytic Enantioselective Epoxidation of Some Aryl-Substituted Vinylidenebisphosphonate Esters: On the Way to Chiral Anti-Osteoporosis Drugs - Download this document for free, or read online. Document in PDF available to download.

Dipartimento di Scienze Molecolari e Nanosistemi, Università Ca’ Foscari Venezia, via Torino 155, 30170 Venezia Mestre, Italy





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Academic Editor: Veronique Nardello-Rattaj

Abstract The synthesis of a new class of epoxide derivatives from prochiral vinylidene bisphosphonate VBP precursors is reported using hydrogen peroxide as the terminal oxidant. The reaction is carried out using a series of possible organic activators having a basic character, with the best results being observed using quinine and sparteine. These activators not only provide from good to excellent epoxide yields with a large variety of VBPs, but also interesting enantioselectivities in the 67%–96% ee range, at least in the case of the Ph and m-MeO–Ph VBP derivatives, opening the way to a number of chiral anti-osteoporosis potentially active pharmaceutical ingredients. View Full-Text

Keywords: bisphosphonates; epoxidation; hydrogen peroxide; enantioselectivity; quinine; sparteine bisphosphonates; epoxidation; hydrogen peroxide; enantioselectivity; quinine; sparteine





Author: Andrea Chiminazzo, Laura Sperni, Alessandro Scarso and Giorgio Strukul *

Source: http://mdpi.com/



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