| 主权项 |
1. A process to prepare a ribonolactone compound of Formula (I): comprising the step of reacting a fructosamine compound of Formula (II): in the presence of a calcium salt in a nonaqueous reaction medium, to provide said ribonolactone compound of Formula (I); wherein R1 and R2 are independently selected from C1-6 alkyl, benzyl, allyl, phenyl, or naphthyl, each substituted with zero to 6 substituents independently selected from halogen, —OH, C1-12 alkyl, —O(C1-6 alkyl), —NO2, —NH2, —N(C1-6 alkyl)2, —CO2H, —CO2(C1-6 alkyl)2, benzyl, allyl, and/or phenyl; or alternatively, R1 and R2 along with the nitrogen atom to which they are attached form a cyclic amine selected from pyrrolidine, piperidine, 1-azacycloheptane, morpholine, or piperazine, wherein said cyclic amine is substituted with zero to 6 substituents independently selected from halogen, —OH, C1-12 alkyl, —O(C1-6 alkyl), —NO2, —NH2, —N(C1-6 alkyl)2, —CO2H, —CO2(C1-6 alkyl)2, benzyl, allyl, and/or phenyl. |
