SEARCH Articles Figures Tables Alkaloids pyrrolidine ring Pyrrolidine ring Pyrrolidine ring construction Pyrrolidine ring construction synthesis Pyrrolidine ring geometry Pyrrolidine ring of nicotine Pyrrolidine ring synthesis Pyrrolidine ring, intramolecular cyclization Pyrrolidine-containing ring systems Pyrrolidines ring closure Pyrrolidines ring expansion Pyrrolidines ring synthesis Pyrrolidines ring systems Pyrrolidines rings Pyrrolidines rings RING REARRANGEMENT METATHESIS (RRM) A NEW CONCEPT IN PIPERIDINE AND PYRROLIDINE SYNTHESIS