Efficient Syntheses of Pyrofolic Acid and Pteroyl Azide, Reagents for the Production of Carboxyl-Differentiated Derivatives of Folic Acid
摘要:
Reaction of folic acid (1) with excess trifluoroacetic anhydride provides access to both the previously unknown N-10-(trifluoroacetyl)pyrofolic acid (8) and pyrofolic acid (9). Reaction of either of these materials with hydrazine selectively affords pteroyl hydrazide (13), which may be oxidized to pteroyl azide (27) on a large scale (62% overall from 1 without the need for chromatography). Treatment of 27 with differentially protected glutamates provides a convenient and high-yielding synthesis of differentially protected, optically pure folates.
(EN) Novel folic acid derivatives and their use in preparation of $g(g)-esters of folic acid via a pteroyl azide intermediate are described. Folic acid $g(g)-esters are useful intermediates in the synthesis of folic acid conjugates capable of binding folate receptors $i(in vitro) and $i(in vivo).(FR) Cette invention se rapporte à de nouveaux dérivés d'acide folique et à leur utilisation dans la préparation de $g(g)-esters d'acide folique via un intermédiaire à base d'azide ptéroyle. Les $g(g)-esters d'acide folique constituent des intermédiaires utiles dans la synthèse de conjugués d'acide folique capables de fixer les récepteurs de folate $i(in vitro) et $i(in vivo).