Zanthoxylum arborescens

Two new quinazoline alkaloids of unusual structure were obtained from the seed husks of Zanthoxylum arborescens.12 Infrared, H n.m.r., and mass spectroscopy showed that the major alkaloid was a quinazolone containing a phenethyl substituent. The 13C n.m.r. spectrum indicated that an iV-methyl rather than an O- methyl group was present, but the spectroscopic studies did not distinguish between structures (19 R = H) and (20 R = H). The alkaloid was shown to be the iV-phenethyl derivative (20 R = H) by synthesis (Scheme 4), and a minor... 

Grina, JA, etai 1982. Constituents aiZan-thoxylum. Part 7. Old and new alkaloids from Zanthoxylum arborescens" Journal of Organic Chemistry 47(13) 2648-2651. 

C.vH.eNzOa 100-102 (148-150) Hydrangea umbellata Rheder (151) Zanthoxylum arborescens... 

Dreyer and Brenner 62) isolated two new quinazoline alkaloids from seed husks of Zanthoxylum arborescens. The major compound, C17H16N2O2 exhibits a blue fluorescence on TLC. In the H-nmr spectrum the downfield aromatic quartet at 8 8.12 (J = 7.1 Hz) and a one-proton triplet at 8 7.8 (J = 7 Hz), each further split (J = 1 Hz) suggest the presence of four adjacent aromatic protons on an ortho-substituted benzene ring. The aromatic quartet farthest downfield at 8 8.12 indicates the presence of a / r/-related carbonyl group. Two two-proton multiplets (8 2.93—4.40) are consistent with the presence of a 2-phenylethyl system. Other nmr data, in light of the mass spectrum, suggest the presence of an N-methylanthranilic acid system. These characteristics could be assembled in two different ways, leading to structures (7) (Chart 1) and (31). C-spectroscopy and synthesis from N-methylisatoic anhydride and 2-phenylethylamine finally allowed elucidation of the structure. The synthetic product, l-methyl-3-(2 -phenylethyl)-lH,3H-quinazolin-2,4-dione (7) was identical with the alkaloid. 

I 4,7-diOMe, 8-OCH2CH = CMe2 Teclea natalensis [39], T. simplicifolia [22], Zanthoxylum arborescens [16]... 

Zandooxylum arborescens Rose-246,402 Zanthoxylum sp.—420 Zomia latifalia DC.-421 Zygophylitem fab ago L.-262-3... 

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