تفاعل #362910

معادلة التفاعل

synadenol

synguanol

Adenosine

synadenol

synguanol

→

(R)-(−)-synadenol

المذيبات

dichloromethane methanol

dichloromethane methanol

—

Na2HPO4

ظروف التفاعل

المعالجة

1. 1
   أخرىwas briefly sonicated
2. 2
   workup.ADDITIONAddition of another two portions of enzyme (30 mg every 24 h)
3. 3
   أخرى40 mL) until no UV absorption
4. 4
   أخرىevaporated

الإجراء التجريبي

A suspension of racemic synadenol (1, B=adenin-N9-yl, 200 mg, 0.92 mmol) from Example 5 in 0.05 M Na2HPO4 (pH 7.5, 100 mL) was briefly sonicated. Adenosine deaminase from calf intestine (Type II, Sigma Chemical Co., St. Louis, Mo., 30 mg, 45 units) was added and the mixture was stirred at room temperature. The progress of the reaction was followed by TLC in dichloromethane-methanol (9:1). The deamination stopped after 72 h and the ratio of synadenol (1, B=adenin-N9-yl):synhypoxanthol (1, B=hypoxanthin-N9-yl) was 7:3 as determined by UV spectrophotometry of the eluted spots. Addition of another two portions of enzyme (30 mg every 24 h) did not improve this ratio. The mixture was lyophilized and the resultant product was sonicated with several portions of dichloromethane-methanol (1:1, first 100 mL and then 40 mL) until no UV absorption was detectable in the solvent. The filtrate and washings were combined and evaporated. The residue was adsorbed on silica gel (4 g) and loaded on a column made of the same material. Chromatography using dichloromethane—methanol (9:1) as an eluent afforded (R)-(−)-synadenol (1, B=adenin-N9-yl), 135 mg, 66.5 %), [α]25D−59.1° (c 0.04, MeOH) and elution with dichloromethane—methanol (4:1) gave (S)-(+)-synhypoxanthol (1, B=hypoxanthin-N9-yl), 85 mg, [α]25D91.80° (c 0.1, MeOH).

المصدر