Abstract
The title compounds (17 and 21) were prepared in good yield by synthesis of the phosphonate diester acetals, deesterification with chloro- or bromotrimethylsilane, hydrolysis of the acetal group and formation of the characterized Ba salts. The 3-C aldehydophosphonic acids (17 and 21) were potent inhibitors (Ki = 2 .times. 10-6) of pyridoxal phosphate (PPal) binding to apoaspartate aminotransferase (AAT) and are believed to span between and bind to the enzymic functional groups which bind the aldehyde and phosphate groups of PPal.