Abstract
Guaiazulene (1, 4-dimethyl-7-isopropylazulene) reacted with malonyl dichloride in the absence of a Lewis acid to afford 3-(guaiazulen-3-yl)-3-oxopropionylchloride (1), which was converted by treatment with water into 3-(guaiazulen-3-yl)-3-oxopropionic acid (2) and 3-acetylguaiazulene (3). Upon treatment of 1 with some alcohols and aromatic amines, the corresponding esters (4) and amides (5) were obtained, respectively. The reaction of methyl 3-(guaiazulen-3-yl)-3-oxopropionate (4a) with hydrazine gave 3-(guaiazulen-3-yl)-3-oxopropionylhydrazide (6), which was easily cyclized into 5-(guaiazulen-3-yl)-2, 3-dihydropyrazol-3-one (7).
