Tetraester 7 reacted with 1 molar equiv of bromine in carbon tetrachloride solution to give a highly crystalline product 10 in 93.3% yield. Electron-impact mass spectral analysis of product 10 showed an apparent molecular ion at m/e 504 (100%) corresponding to C22H1608S3, implying loss of one sulfur atom and two hydrogen atoms from tetraester 7 (C= H, 808&, and no incorporation of bromine. The chemical ionization mass spectrum of ...