バシシン

解説(R)-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazolin-3-ol．C11H12N2O(188.23)．ペガニンともいう．キツネノゴマ科Alhatoda vasia，ハマビシ科Peganum harmalaに含まれるキナゾリンアルカロイド．(S)-バシシンは白色の針状晶．融点212 ℃．[α]14D－254°(クロロホルム)．有機溶媒に可溶，水に難溶．酸性で徐々にラセミ化する．マメ科Galega officinalisには(S)-バシシンが含まれており，(RS)-バシシンは融点209 ℃，[α]24D＋203°で合成されている．森北出版「化学辞典（第2版）

説明This quinazoline alkaloid was first isolated from the leaves of Adhatoda vasica Nees by Hooper and subsequently discovered in Peganum harmala under the name Peganine. The base is optically inactive although Spath and Kesztler have reported the isolation of the (-)-form from the fresh leaves of A. vasica and Rosenfeld and Kolesnikow have obtained the same form from the flowers and stems of Peganum harmala. The salts are readily obtained crystalline, e.g. the hydrochloride dihydrate, m.p. 208°C (dry); hydriodide dihydrate, m.p. 195°C (dry); picrate, m.p. 199°C (dec.) and the methiodide, m.p. 187°C.With AcOH, the alkaloid gives an anomalous acetyl derivative, m.p. 165°C, subsequently shown to be N-acetylpedadiene. Oxidation with KMn04 gives 4-quinazolone and 4-keto-3 :4-dihydroxyquinazolyl-3-acetic acid, the latter characterized as the methyl ester, m.p. 152°C.The crude drug from A. vasica is used in India as a remedy for asthma while the pure alkaloid acts as a bronchodilator.