General Experimental Procedures. Optical rotations were determined
on a JASCO P-1020 digital polarimeter or an Atago Polax-D
polarimeter. IR spectra were recorded on a Perkin-Elmer RX1 FT-IR
spectrophotometer. UV spectra were obtained on a Shimadzu UV-
3101PC spectrophotometer. 1H and 13C NMR spectra were recorded
in CDCl3 using TMS as internal standard on a JEOL JNM-LA 400