We report the synthesis and antimicrobial evaluation of some 4-amino-2,3-dihydro-2-imino-3-(1-iminododecyl)thiazole- 5-carbonitrile derivatives 8a-e. The target compounds were synthesized via a multi-step methods involving the conversion of dodecanoyl chloride to the corresponding dodecanimidoyl chlorides 4a-e (via dodecanamide derivatives) and then to the imidoylisothiocyanate derivatives 5a-e followed by their conversion to thiourea derivatives and finally to the desired thiazole derivatives. All the synthesized compounds were characterized by IR and 1HNMR spectral data and elemental analysis. Most of these compounds showed moderate antibacterial and antifungal activity when tested in vitro.