Thiaphysovenol Phenylcarbamates: X-Ray Structures of Biologically Active and Inactive Anticholinesterase Agents

The X-ray structure of the biologically active phenylcarbamate (4), and the biologically inactive phenylcarbamate (5) of the thiaphysovenol series, reveal that the two aromatic ring systems are differently oriented towards each other. The absolute configuration of both compounds, determined by using the anomolous scattering from the sulfur atoms, was found to be (3aS-cis)