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Studies directed toward the process research, development, and scale-up preparation of the potential r v β 3 integrin antagonist 1 are described. A convergent approach is detailed wherein tetrahydropyrimidine hydroxybenzoic acid 2 is linked to the β-amino acid ester 3 via a diisoproylcarbodiimide, catalytic HOBt coupling reaction. Saponification of the resulting ethyl ester, isolation of the corresponding zwitterion, H 3 PO 4 salt formation, crystallization, and acetonitrile-to-acetone exchange give rise to 1 as a crystalline monohydrate in 67% overall yield from 4.