barium(2+);methanolate

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A 30-g. portion of the benzodioxan compound prepared in Example 1C was dissolved in 300 ml. of warm benzene, diluted with 600 ml. of methanol containing 70 mmol. of barium methoxide, and then stored 18 hours at 5° C. After adding 10 g. of ammonium acetate, volatiles were evaporated and the residue was extracted with two 500-ml. portions of chloroform. The chloroform was washed once with 500 ml. of water, the water was reextracted with 500 ml. of chloroform, and the combined chloroform extracts were washed once with 300 ml. of water. Evaporation and crystallization from diethyl ether-n-hexane gave the neutral form of the novel sweet compound (23 g., 95%), m.p. 105°-106° C. After adding 10 g of ammonium acetate, volatiles were evaporated the residue was extracted with two 500-ml The chloroform was washed once with 500 ml of chloroform, and the combined chloroform extracts were washed once with 300 ml Evaporation and crystallization from diethyl ether-n-hexane gave the neutral form of the novel sweet compound (23 g., 95%), m.p. 105°-106° C.

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A 30-g. portion of the benzodioxan compound prepared in Example 1C was dissolved in 300 ml. of warm benzene, diluted with 600 ml. of methanol containing 70 mmol. of barium methoxide, and then stored 18 hours at 5° C. After adding 10 g. of ammonium acetate, volatiles were evaporated and the residue was extracted with two 500-ml. portions of chloroform. The chloroform was washed once with 500 ml. of water, the water was reextracted with 500 ml. of chloroform, and the combined chloroform extracts were washed once with 300 ml. of water. Evaporation and crystallization from diethyl ether-n-hexane gave the neutral form of the novel sweet compound (23 g., 95%), m.p. 105°-106° C. After adding 10 g of ammonium acetate, volatiles were evaporated the residue was extracted with two 500-ml The chloroform was washed once with 500 ml of chloroform, and the combined chloroform extracts were washed once with 300 ml Evaporation and crystallization from diethyl ether-n-hexane gave the neutral form of the novel sweet compound (23 g., 95%), m.p. 105°-106° C.

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of 1-(2-O-nitro-3,5-di-O-acetyl-β-D-arabinofuranosyl)-N4 -acetylcytosine (10 g., 24 mmol) in anhydrous methanol (425 ml) under an atmosphere of dry nitrogen was added 1.9N barium methoxide (5 ml., 9.5 meq) in methanol. The reaction mixture was stirred at room temperature under an inert atmosphere for one hour and was then neutralized with a cation exchange resin (90 g., Bio-Rex 70/H+, 100-200 mesh )in the presence of water (5 ml). The resin was separated by filtration and washed with methanol. The combined filtrate and washings were evaporated under reduced pressure to yield crude 1-(2-O-nitro-β-D-arabinofuranosyl)cytosine (6.60 g., 95%), which was crystallized from H2O to yield pure 1-(2-O-nitro-β-D-arabinofuranosyl)cytosine (5.97 g., 86%): m.p. 151.3°-152.7° C.; The resin was separated by filtration washed with methanol The combined filtrate and washings were evaporated under reduced pressure to yield crude 1-(2-O-nitro-β-D-arabinofuranosyl)cytosine (6.60 g., 95%), which was crystallized from H2O

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A 30-g. portion of the benzodioxan compound prepared in Example 1C was dissolved in 300 ml. of warm benzene, diluted with 600 ml. of methanol containing 70 mmol. of barium methoxide, and then stored 18 hours at 5° C. After adding 10 g. of ammonium acetate, volatiles were evaporated and the residue was extracted with two 500-ml. portions of chloroform. The chloroform was washed once with 500 ml. of water, the water was reextracted with 500 ml. of chloroform, and the combined chloroform extracts were washed once with 300 ml. of water. Evaporation and crystallization from diethyl ether-n-hexane gave the neutral form of the novel sweet compound (23 g., 95%), m.p. 105°-106° C. After adding 10 g of ammonium acetate, volatiles were evaporated the residue was extracted with two 500-ml The chloroform was washed once with 500 ml of chloroform, and the combined chloroform extracts were washed once with 300 ml Evaporation and crystallization from diethyl ether-n-hexane gave the neutral form of the novel sweet compound (23 g., 95%), m.p. 105°-106° C.