STEREOCHEMICAL STUDIES - LVII. SYNTHESIS OF OPTICALLY ACTIVE COMPOUNDS BY THE NOVEL USE OF MESO-COMPOUNDS -1. EFFICIENT SYNTHESIS OF TWO STRUCTURAL TYPES OF OPTICALLY PURE PROSTAGLANDIN INTERMEDIATES.

Article abstract of DOI:10.1016/0040-4020(80)80160-8

With an aim to overcome several inefficient aspects of ordinary methods of preparing optically active compounds, we have developed a new method which recommends utilization of symmetrically functionalized meso-compounds in place of racemic compounds.As shown in Scheme 1, when the meso-compound (I) is monofunctionalized by an optically active functional group (A) and each of the formed diastereomers (II and III) is subjected to further chemical elaborations including protective group transposition, it is theoretically possible to convert the total amount of the starting material (I) into the requisite optically pure product (VI or VII) by selecting synthetic schemes.By employing this novel concept, two structural types of the prostaglandin intermediates ((-)- and (+)-2a,b) have been prepared from the meso-diols (1a,b) by way of the two diastereomeric monoesters (13a,b and 14a,b) which are produced by the reactions 1a,b with N-mesyl- and N-phthaloyl-(S)-phenylalanyl chloride (3a,b).