extract was washed with water 200 ml and brine 400 ml which were subsequently back extracted with chloroform 200 ml the chloroform phases were combined and dried over sodium sulfate the solution was filtered the solvent removed under reduced pressure and the product dried in vacuo the dry residue 200 mg was dissolved in chloroform 5 ml followed by the addition of 3m methanolic hydrochloric acid 3 equivalents and ether 5 ml and left at u2212 20 u00b0 c overnight the solution was filtered dried in vacuo and 145 mg of the 9 deoxy 9 amino daunomycinone hydrochloride obtained step 2b ritter intermediate hydrolysis experiment 2 450 mg of the ritter intermediate of example 2 was dissolved in 3 n sulfuric acid 45 ml and heated at 60 u00b0 c for 30 h the after treatments were carried out in the same manner as in experiment 1 2 200 mg of the obtained 9 deoxy 9 amino daunomycinone was dissolved in chloroform 5 ml followed by the addition of 3m methanolic hydrochloric acid 3 equivalents and ether 5 ml and left at u2212 20 u00b0 c overnight the solution was filtered dried in vacuo and 115 mg of the 9 deoxy 9 amino daunomycinone hydrochloride obtained step 2c ritter intermediate hydrolysis experiment 3 700 mg of the ritter intermediate of example 2 was treated as in experiment 1 using a mixture of 525 ml of tetrahydrofurane 116 7 ml of concentrated sulfuric acid and 58 3 ml of water and heating at 60 u00b0 c for 7 h 600 mg of the 9 deoxy 9 amino daunomycinone was obtained and dissolved in chloroform 10 ml after the addition of 3 m methanolic hydrochloric acid 2 equivalents and ether 10.