A New phenylquinolizidol of Heimiasalicifolia

Abstract

Les auteurs sont seuls responsables des opinions exprim6es dans ces br6ves communications. -Ftir die Kurzmitteilungen ist ausschliesslich der Autor verantwortlich. -Per le brevi comunicazioni 6 responsabile solo l'autore. -The editors do not hold themselves responsible for the opinions expressed in the authors' brief reports. -OTBeTCTBeHH0CTb 3aK0p0TKHe C006meHH~ HeC~T HC~amqHTenbH0 aBT0p.--]~1 responsable de los informes reducidos, est& el autor. A New Phenylquinolizidol of Heimia salicifoliaIn continuing our studies on the alkaloids of Heimia salicifolia Link and Otto we have established the presence of 2-hydroxy(a)-4-(3-hydroxy-4-methoxyphenyl) (e)-trans- During investigations of the sequential appearance of the alkaloids of H. salici/olia the presence of two unknown alkaloids in 7-day-old seedlings was observed ~. We continued with these studies and have determined that one of the compounds is the phenylquinolizidol I by direct comparison with a synthetic sample. We found that I accumulates only in relatively young seedlings. It could not be found in the seeds, in 2-week-old seedlings a in 5-6-month-old plantlets, or in mature plants.Seedlings (5-day-old) and some ungerminated seeds were dried (6.7 g), and extracted (blender) with acetate buffer at pH 5. Undesirable material was eliminated from this solution with CttC1 a. CHC13-MeOH (4:1) extraction at pIK 8.5-9, gave the desired alkaloids (25.7 mg). R2 I, RI =OH, R2=HII, R1 = I'1, R2 = OH OCH3 III, R~, R=, = 0 Compound I, (0.6 rag) was obtained by preparative TLC [A1203GF254, NH~ saturated benzene-MeOH (190:10), double development, followed by NH~ saturated EtOAcEtOtt (210:2.5)]. That the natural compound was identical with the synthetic compound was verified by TLC (3 alumina and 7 silica gel systems) and by mass spectrometry.I possesses the same stereochemistry (C-2 oxygen axial, phenyl ring equatorial, nitrogen spin pair axial) as all the Heimia alkaloids. We have not detected the equatorial alcohol in any plant material analyzed.Condensation of pelletierine with isovanillin 6, ~ gave

The biosynthesis of the Lythraceae alkaloids. I. The lysine-derived fragment

“…Manilich condensation of pelletierine with a C6-C, unit, isovanillin, a reaction which has been employed in biomimetic synthesis (1 5-1 7), yields the phenylquinolizidinone (6). This compound, together with the corresponding alcohol, has been detected in Heirnin salicifolia (16,17). It represents the structural core of the first group of Lythraceae alkaloids.…”

Biosynthesis of Lythraceae Alkaloids: Incorporation of DL-{4,5-13C2, 6-14C}lysine and cis-and trans-4-(3,4-dihydroxyphenyl)-quinolizidin-2-one Into Vertine and Lythrine

“…Enrichment of the metabolite is then detected by the presence of satellites flanking the natural abundance singlets in the 13C-nmr spectrum of the metabolite; very low levels of enrichment are clearly discernible (4)(5)(6). Wick feeding of DL-[4,5-13C2, 6-14C}lysine (99-8% doubly labeled with 13C, 8.5 µ , 18.7 mg) to Heimia salicifolia Link & Otto (Lythraceae) plants gave lythrine [10] and vertine [11] (analyzed as its 0-methyl ether 12) with, respectively, 0.35 and 0.14% enrichment of label as measured by 13C-nmr spectroscopy; closely similar values were obtained through radioactivity measurements.…”

The biosynthesis of the Lythraceae alkaloids. II. The phenylalanine-derived fragments

“…After elution of a small amount of a minor component, the major product emerged. Combination and evaporation of the fractions gave a colourless gum (154 mg) which was pure by 'H nmr and on three tlc systems but could not be obtained crystalline; 'H nmr (CDCl,) 6: 0.93 (t, J = 7 Hz, 3H, CH2CH3) 2.58 (broad t, J = 7 Hz, 2H, Ar-CH,), 3.57 (s, 3H, OCH,) oxidation of desoxytetralrydrodirnetlryldecodir~e (14) to the corresponding ketone, dehydrodesoxytetra/~ydrodimet/~yldeco-dine (IS)-Standard Jones' reagent (0.9 mL) was added dropwise to an ice cold solution of the alcohol (14) (150 mg) in acetone. The cooled mixture was stirred 10 min, excess reagent was destroyed by addition of 2-propanol(1 mL), and the solution poured into 0.01 M hydrochloric acid (30 mL).…”

“…Indeed, compounds corresponding in structure to the phenylquinolizidinone (1) (14), the phenylquinolizidinols (2, and its cis-fused isomer) (14,15) and to phenylpropanoid esters of the latter (e.g. 4) (16,17) have been found in H. salicifolia.…”