1) T. Hamasaki, Y. Sato and Y. Hatsuda, Agr. Biol. Chem., 39, 2337 (1975);
T. Hamasaki, Y. Sato, Y. Hatsuda, M. Tanabe and L. W. Cary, Tetrahedron Letters, No. 9, 659 (1975).
2) The atomic scattering factors were taken from the “International Tables for X-ray Crystallography,” Vol. III, Kynoch Press, Birmingham, 1962, p. 202.