1-(Bromoacetyl)-3-methylazulene (1a) and methyl 3-(bromoacetyl)azulene-1-carboxylate (1b) reacted with thioamides 30 and thioureas 3c,d in boiling ethanol to give the corresponding (4-thiazolyl)azulenes 4a-d and 5a-d in good yields, respectively. The reactions of dibromoacetyl-substituted azulene (2) also gave (4-thiazolyl)azulenes 5a-d in lower yields and the azulene 2 was recovered. By heating compounds 5a-d in 100% phosphoric acid, the ester group was eliminated to yield 1-(4-thiazolyl)azulenes 6a-d. Compounds la,b reacted with thiosemicarbazones 7a-f to afford [(2-alkylidenehydrazino)thiazol-4-yl]azulenes 8a-f and 9a-f in moderate to high yields via their hydromides.