Structure of amidothiophosphorylation products derived from 2,5-O-methylene-D-mannitol

The reaction of 2,5-O-methylene-D-mannitol with tris(N-diethylamino)phosphine and powdered sulfur affords diastereomeric l,34,6-bis-O-(N-diethylaminothiophosphoryl)-2,5-O-methylene-D-mannitols. The absoluteR,R-configuration of one of them was determined by X-ray analysis. In this product one of the two 1,3,2-dioxaphosphorinane rings is in the boat conformation, whereas the other is in the chair conformation. The central 1,3-dioxepane ring adopts an asymmetric chair conformation. All of the three condensed heterocycles aretrans-fused. The manifestations of the anomeric effect in amidothiophosphates of monosaccharides are discussed.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 406–409, February, 1993.