Synthesis of some new Mannich bases, 2(thiazolylaminobenzyl)-1-naphthols (I) and 1(thiazolylaminobenzyl)-2-naphthols (II) are described. Condensation of 4,5-disubstituted-2-aminothiazoles and the appropriate aldehyde with 1-naphthol gives (I), while condensation with 2-naphthol gives (II). Their structures have been ascertained by spectroscopy and by synthesis from the dibromoderivative of 2-arylidene-1-tetralone and the corresponding 2-aminothiazole.