On the other hand, PCl can be usefully converted to its monoamide, which in turn undergoes alkylation or arylation.

A phosphoramidite (RO)PNR is a monoamide of a phosphite diester.

In industry, PABA is prepared mainly by two routes: reduction of 4-nitrobenzoic acid and the Hoffman degradation of the monoamide derived from terephthalic acid.

Thus, the two substrates of this enzyme are monoamide of a dicarboxylic acid and HO, whereas its two products are dicarboxylate and NH.