... 39(9) 2308–2315 (1991) Vol. ... One is a chemical modification to find a compound which shows antitumor activity at lower dosage, and this paper deals with the structure ... TS (CONHCONH STS -- eeS NHC(O)NH STS methol B X ү X ү ү ү Chart 1 (Ç) 1991 Pharmaceutical Society of ...