AWARDEE OF CHEMISTRY PRIZE

ZHANG PANG

Abstract

Zhang Pang, organic chemist, born on August 25, 1917, in Nanjing, Jiangsu Province.  Degrees: B. A., 1942, Department of Chemistry, Nationa1 Southwest Associate University, Kunming, Yunnan Province; Ph. D., 1949, Department of Chemistry, Cambridge University, Cambridge, U.K.His Ph.D. thesis dealt with syntheses related to carbohydrate and nucleoside. He returned the same year and worked as associate professor in former Yenching University and then in Peking University and was promoted as professor in 1956.
His research covers synthesis of organic compounds and studies of novel synthetic methods and organic reactions. He published papers on the syntheses of anhydro sugars derived from pentomethylosides, of 5-hydroxypyrimidines, of novel cyanine dyes contaning dihydrofurfurylium ring, and of vitamin B6 by a route leading to direct formation of 3-hydroxypyridines. In connection with polypeptide synthesis, he proposed a synthesis of N,N-bis ［tris (methoxymethyl) methyl］ carbodiimide which was shown soluble in both organic solvents and in water, and also in their mixtures of any proportion. The oxacyclobutan-3-ol was synthesized to show that its tosylate can undergo Finkelstein reaction rather than the benzaldehyde-1, 3-glycerylacetal tosylate does not.
Novel method and new reaction were found by him as follows. A method of synthesizing α,β-unsaturated ketones was devised via acylation of an enamine followed by catalytic hydrogenation and acid hydrolysis with concurrent dehydration.
He found that 1,3-dimethoxyacetone rearranges on keeping to yield methy1 glyoxal dimethyl acetal. Further study showed that the rearrangement constitutes a general method of synthesizing substituted methylglyoxal dimethyl acetals. Mechanistic study showed that it is a sigmatropic process.
Lastly, Zhang worked out a synthetic route for perylenequinone bisacetic acid differing from natural perylenequinones only by side chains with carboxyl on one hand and different substituents such as acetonyl on the other. It was adapted by three research groups to afford the synthesis of phleichrome, a natural perylenequinone responsible for protein kinase C inhibition.
As a member of Chinese Chemical Society, he had been responsible for the section of organic synthesis and organized conferences. He edited “Progress of Organic Synthesis" (1991) and Peking University Press published his collected papers (2000).