Abstract: Derivatives of 3-acylamino-3-deoxyallose represented by the following formula: ##STR1## wherein R.sup.1, R.sup.2, R.sup.3 and R.sup.4 may be hydrogen atoms, or R.sup.1 and R.sup.2, and R.sup.3 and R.sup.4 may be in combination an isopropylidene group, R.sup.5 represents a hydrogen atom or alkyl group, and R.sup.6 represents a hydrogen atom or acyl group, are disclosed. One of the typical compound 3-deoxy-3-(3-tetradecanoyloxytetradecanoylamino)-1,2:5,6-di-O-isopropylide ne- .alpha.-D-allofuranose is prepared by reacting 3-tetradecanoyloxytetradecanoic acid and 3-amino-3-deoxy-1,2:5,6-di-O-isopropylidene-.alpha.-D-allofuranose in the presence of N,N'-dicyclohexylcarbodiimide, as a dehydrating agent. The compound has an excellent carcinostatic activity.

Abstract: Disclosed herein are Fredericamycin A derivatives, each, represented by the following general formula (I): ##STR1## wherein R means a hydrogen atom or acyl group, A denotes ##STR2## and dotted bonds are optional, with a proviso that when A is ##STR3## or the dotted bonds are contained, R is other than hydrogen atom. They have excellent antibacterial and antitumor activities and at the same time, are extremely stable compared with Fredericamycin A.