| abstract |
Benzyl or phenyl guanidobenzoates, potent trypsin inhibitors, preventing activation of trypsinogen. G3A. are new cmpds. of formula (I) (where R and/or R' are H, alkyl, aryl, NO2, NH2, NH alkyl N(alkyl)2, alkoxy, carboxy, carbalkoxy or halogen, and n is zero or 1), produced by converting 3- or 4- guanidobenzoic acid hydrochloride into the acid chloride, and reacting this at 100-200 degrees C (pref. 100-150 degrees C) with a hydroxy cpd. of the general formula (II): by co-melting both components or in an inert solvent, pref. glacial acetic acid. On removing unreacted substances by extraction with solvents (pref. ether, ethanol or an ether-ethanol mixture), the crude product is purified by crystn. from anhydrous or aqs. ethanol, acetic ester or a mixture of acetone and ether. Advantages offered by the method are: cpds. (I) are obtained in a one-step process, in a short reaction period, in yields mostly over 80%, and the starting materials are easily available or obtainable by simple procedures e.g. benzyl alcohol (formula (II); R, R' = H, n=1), phenol (formula (II); R, R'=H, n=O). |