Gerphytine, a new furanoquinoline alkaloid from Haplophyllum griffithianum

Abstract

A series of known alkaloids and the new base gerphytine were isolated from total alkaloids from the aerial part of Haplophyllum griffithianum growing in Surkhandarcya Oblast, Republic of Uzbekistan. Gerphytin was identified based on spectral data and an x-ray crystal structure analysis as a furanoquinoline derivative and had the structure 7-O-allyl-4,8-dimethoxyfuranoquinoline.The plant genus Haplophyllum (Rutaceae) has for a long time been used in folk medicine as an anesthetic and woundhealing agent for burns and tumors, toothache, and stomach and skin diseases and as a treatment for respiratory organs and several types of cancer [1][2][3]. Extracts of several Haplophyllum species exhibit cytotoxic activity [4].We reported earlier on the isolation from the aerial part and roots of H. griffithianum Boiss. collected during flowering (Nilu village, Surkhandarcya Oblast) of the quinoline alkaloids skimmanine, dictamnine, dubinine, dubinidine, dubamine, and N-methylhaplofoline [5]. In continuation of studies of the alkaloid composition of the CHCl 3 total alkaloids, we isolated from the aerial part of the plant a new base with mp 93-95°C whose physicochemical properties and spectral data differed from quinoline bases that were previously reported and which we called gerphytine.Gerphytine (1) had formula C 16 H 15 NO 4 ([M] + 285), was soluble in CHCl 3 , poorly soluble in acetone and alcohol, and insoluble in water and base.The IR spectrum of the base exhibited absorption bands at 3139 and 3166 cm -1 due to a furan ring. Absorption bands of hydroxyl and carbonyl groups were missing.The UV spectrum showed two principal absorption maxima including a strong (short-wavelength) band at 249.64 nm (log H 4.7) and a weaker band at 318.91 nm (log H 3.8). The long-wavelength band was split into three peaks and was separated from the first maximum by a deep minimum at 278.0 nm (log H 3.00). This was characteristic of furanoquinoline alkaloids [6,7].The aromatic region of the PMR spectrum of gerphytine had two resonances for protons of a benzene ring at 7.87 and 7.11 ppm (1H each, d, J = 9.3 Hz) and resonances for protons of a furan ring at 7.48 (1H, d, J = 2.8 Hz, H-2) and 6.93 ppm (1H, d, J = 2.8, H-3) that were typical of furanoquinoline-type alkaloids.

Intramolecular Cyclization During Bromination of the Quinoline Alkaloid Haplophyllidine

“…Figure 1 shows the molecular structures of 3-5, which agreed with the absolute configurations. The Flack parameters for these compounds were 0.009(13), 0.027 (11), and 0.020 (7). The presence of the heavy Br atom in the bromination products enabled the absolute configurations to be reliably determined as 7R,8R,10S (3), 7R,8R,10R (4), and 7R,8R,10R (5).…”

“…The middle of the proton spectrum displayed two doublets of doublets at δ 4.18 (dd, J = 7.4, 3.3 Hz, H-7) and 4.44 (dd, J = 7.3, 6.5 Hz, H-10), which were characteristic of protons on a C atom bound to oxygen, and 3H singlets at 3.14 and 4.27 ppm for C-8 and C-4 methoxyls, respectively. The aromatic part of the spectrum had only two 1H doublets with SSCC J = 2.6 Hz at δ H 7.57 ppm (H-2) and 6.95 (H-3) that corresponded to protons of the furan ring [11].…”

Griffithine, a New Furanoquinolone Alkaloid from Haplophyllum griffithianum

“…collected in Surkhandarya Province (Nilu village), Republic of Uzbekistan, during flowering [1,2]. Further separation of the total alkaloids produced a new alkaloid with mp 158-159°C that we called griffithine (1).…”