B. 1-Benzyloxyadenosine'(4.54 g, 10.0 mmoles) was converted to 5-amino-1 4-D- ribofuranosyl4carboxamidine by the published procedure.'A solution of the crude amidine (4b) in 100 ml of 0.1 N NaOH was refluxed for 2 hr before it was neutralized with HOAc,