(C= O, carbamate), 1595 cm-'(C= O at C-9). Anal. Calcd for C20H23N30, S: C, 59.83; H, 5.78; N, 10.46. Found: C, 58.08; H, 5.97; N, 9.32. In another run, 110 mg (0.172 mmol) of 22 and 0.6 mL (0.6 mmol) of the TBAF solution furnished the crude product, which, after being washed with hexane, weighed 60 mg (87%). The NMR spectrum showed little, if any, of the tert-butyl signal, and the IR spectrum was satisfactory. Material of this quality was ...
