Reaction of furylandrostanediol (I) (J Chem Soc (C) 1966, 377) with bromoacetaldehyde diethylacetal (II) in the presence of NaH in refluxing tetahydrofuran provided ether (III). Subsequent acid hydrolysis of ethyl acetal of (III) gave aldehyde (IV), which was reduced to alcohol (V) with NaBH4. Coupling of (V) with phthalimide (VI) under Mitsunobu conditions produced the N-alkylated phthalimide (VII), and further hydrazinolysis yielded primary amine (VIII). The required guanidine function was finally introduced by treatment of (VIII) with 3,5-dimethyl-1-pyrazolylformamidinium nitrate (IX) in boiling EtOH.