Alcaloïdes Pipéridiniques III. Nouveaux Alcaloïdes du Prosopis Africana (Guill. et Perr.) Taub.: Isoprosopinines A et B, Prosophylline, Prosafrine Et Prosafrinine [1]

Abstract

The structures of five new alkaloids have been established: the isoprosopinines A and B, 1 and 2 are homogeneous mixture: isoprosopinine A is (2R, 3S, 6R) 2‐hydroxymethyl 3‐hydroxy 6‐dodecyl 7°‐keto piperidine and isoprosopinine B is (2R, 3S, 6R) 2‐hydroxymethyl 3‐hydroxy 6‐dodecyl 8°‐keto piperidine. Prosophylline 4 is d 2‐hydroxymethyl 3‐hydroxyl 6‐dodecyl 10°‐keto piperidine, prosafrine 9 is (2R, 3R, 6S) 2‐methyl 3‐hydroxy 6‐dodecyl 10°‐hydroxy piperidine and prosafrinine 11, is (2R, 3R, 6S) 2‐methyl 3‐hydroxy 6‐dodecyl 10°‐keto piperidine.

A Configurational Switch Based on Iridium‐Catalyzed Allylic Cyclization: Application in Asymmetric Total Syntheses of Prosopis, Dendrobate, and Spruce Alkaloids

“…[12] Their relative and absolute configuration was disclosed in 1972 by the same group, [13] which also reported the isolation of racemic (AE )-prosophylline in the same year. [14] Since then, various syntheses have been reported for prosopinine, [15,16] prosophylline, [17,18] and their desoxo derivatives. [19,20] Ir-catalyzed allylic amination: The Ir-catalyzed allylic substitution, introduced in 1997, [21] has emerged as a versatile tool for the enantioselective construction of allylic stereocenters.…”

“…The combined organic layers were dried over Na 2 SO 4 and concentrated in vacuo to give pure (by NMR spectroscopy) (+)-(2'S,5'S,6'R)-prosophylline (17.4 mg, 99 %) as a colorless solid showing physical properties that matched those reported. [14,17] Recrystallization from acetone afforded colorless crystals. M.p.…”

In vitro screening on β-amyloid peptide production of plants used in traditional medicine for cognitive disorders

“…Leaved stem decoction is used against epilepsy, bark decoction against dermatose, and heartwood decoction against learning retardation (Adjanohoun et al, 1989). In other countries, the plant is also largely used against dermatoses and for anemia; leaves, roots and stems have been found to contain alkaloids (Kerharo and Adam, 1966;Khuong-Huu-Qui et al, 1972). This heart-wood, frequently used as frotte-dents, is imputrescible, maybe because of the antifungical and anti-insect activity of its extracts; the durability is due to its impenetrability by water: the wood cell lumen is filled by high-rated hydrophobic, non-extractible gums (Gerardin et al, 2004).…”

Stereocontrolled construction of decahydro quinoline ring systems: the case of lepadin alkaloids (Review)

“…2) are assumed to be biosynthetically derived from L-or D-alanine and the corresponding unsaturated fatty acids via a pathway similar to that of sphingosine biosynthesis [10][11][12]. It is reasonable to assume that these linear compounds as well as other as yet unisolated and unknown aminoalcohol lipids are engaged in the biosynthetic machinery that produces a set of diverse cyclic C-18 amino alcohols: the tetrahydroindane based amaminols A and B, the decahydroquinoline based lepadins 1-8, the quinolizidine based pictamine (17), and the piperidine based, plant derived prosafrinine (18) [13][14][15]. Isomerization and shift of four skipped double bonds of E,Z,Z,Z-configuration in crucigasterin 277 (9) to the triple conjugate all-E-configuration, as in the structure 14, can lead to enzymatic asymmetric intramolecular Diels-Alder (IMDA) cyclization to produce amaminol B (15).…”

“…It is reasonable to assume that these linear compounds as well as other as yet unisolated and unknown aminoalcohol lipids are engaged in the biosynthetic machinery that produces a set of diverse cyclic C-18 amino alcohols: the tetrahydroindane based amaminols A and B, the decahydroquinoline based lepadins 1-8, the quinolizidine based pictamine (17), and the piperidine based, plant derived prosafrinine (18) [13][14][15]. Isomerization and shift of four skipped double bonds of E,Z,Z,Z-configuration in crucigasterin 277 (9) to the triple conjugate all-E-configuration, as in the structure 14, can lead to enzymatic asymmetric intramolecular Diels-Alder (IMDA) cyclization to produce amaminol B (15). Such a bio-inspired but two building block approach was realized in our laboratory total synthesis of amaminol A, differing from amaminol B by the configuration of the stereocenter at the amino group [16].…”