Process for the preparation of substituted N-(aryl)-1,2,4-triazolopyrimidine-2-sulfonamides

A process for the preparation of an N-(aryl)-1,2,4-triazolopyrimidine-2-sulfonamide of the formula (V):

• ##STR13## wherein one of A or B is N and the other is C-Z,
• X represents H, R, OR, SR or CF.sub.3,
• Y represents H, R, OR, F, Cl, Br or CF.sub.3,
• Z represents H, R, OR, F, Cl, Br, CF.sub.3 or phenyl,
• R represents a lower alkyl group optionally substituted with one or more halogen or with a lower alkoxy group, and
• Ar is a substituted phenyl group of the formula:
• ##STR14## in which R.sup.1 represents H, F, Cl, Br, R, OR, SR or CO.sub.2 R,
• R.sup.2 represents H, R or OR,
• R.sup.3 represents H, F, Cl, Br, CF.sub.3, CO.sub.2 R or NO.sub.2, and
• R is as previously defined,
• or Ar is a substituted pyrazole group (PRZ) of the formula:
• ##STR15## in which R.sup.4 represents R, phenyl or pyridinyl,
• R.sup.5 represents H, NO.sub.2 or CF.sub.3,
• R.sup.6 represents H, F, Cl, Br, I or CO.sub.2 R,
• R.sup.7 represents H or R, and
• R is as previously defined,
• consisting of contacting a substituted 1,2,4-triazolopyrimidine-2-sulfonyl halide of the formula ##STR16## wherein A, B, X, Y, Z and R are as previously defined, with an aryl amine of the formula
• ArNH.sub.2
• wherein
• Ar is as previously defined,
• in an inert aprotic organic solvent in the presence of a pyridine base and of a catalytic amount of dimethyl sulfoxide (DMSO).