Page 1. Tctrahcdrcm Letters, Vo1.31, No.49, pp 1223-7226 195X ao4o4039/90 $3.00 + .oo Pr+d in Great Britain Pergmon Press plc ... c) J. Mauger, T. Nagasawa and H. Yamada, J. Biotechnd., 1988487. 7. a) C. Bengis-Garber and AL Gutman, Tetrahedron Lett., l988,29,2589. ...