摘要 |
A method of removing the triphenylmethane protecting group from 1- triphenylmethyl-5-(4'-subst. methyl-1,1~-biphenyl-2-yl)-1H-tetrazoles of general formula I wherein R represents the groups of formulae and where R1, R2 and R3 can be H, a halogen, an unbranched or branched C1-C5 alkyl, C1-C5 hydroxyalkyl, Cl-C5 alkoxy, C1-C5 alkoxymethyl or benzyl, or wherein R2 and R3 can form together a saturated or unsaturated C5-C7 ring, optionally an unsubstituted or substituted aromatic ring, is carried out by solvolysis in a simple anhydrous Cl to C5 alcohol in a neutral or slightly basic medium. The method is suitable for the preparation of drugs, such as the potassium salts of losartan, irbesartan or valsartan or candesartan cilexetil.
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