62024-31-1Relevant academic research and scientific papers
Biomimetic synthesis of 2-substituted N-heterocycle alkaloids by one-pot hydrolysis, transamination and decarboxylative Mannich reaction
Galman, James L.,Slabu, Iustina,Parmeggiani, Fabio,Turner, Nicholas J.
supporting information, p. 11316 - 11319 (2018/10/24)
Heterocycles based on piperidine and pyrrolidine are key moieties in natural products and pharmaceutically active molecules. A novel multi-enzymatic approach based on the combination of a lipase with an α,ω-diamine transaminase is reported, opening up the synthesis, isolation and characterisation of a broad range of 2-substituted N-heterocycle alkaloids.
Mechanistic studies on diamine oxidase: oxidation of α,ω-diamines does not involve an enamine intermediate
Gavin, Stephen S.,Equi, Angela M.,Robins, David J.
, p. 31 - 34 (2007/10/02)
Three β,β,β',β'-2H4-labelled α,ω-diamines were synthesized and incubated with pea seedling diamine oxidase.The aminoaldehydes formed by oxidative deamination cyclized to the corresponding imines, which were trapped with benzoylacetic acid.In all three cases the acetophenone derivatives produced were shown by NMR and mass spectrometry to contain four deuterium atoms.The retention of all four deuterium atoms demonstrates that oxidative deamination of α,ω-diamines catalyzed by pea seedling diamine oxidase does not involve an enamine intermediate as previously suggested.
PEA-SEEDLING DIAMINE OXIDASE: APPLICATIONS IN SYNTHESIS AND EVIDENCE RELATING TO ITS MECHANISM OF ACTION
Cragg, John E.,Herbert, Richard B.,Kgaphola, Mashupye M.
, p. 6907 - 6910 (2007/10/02)
Diamines (6)-(8) and (11) act as acceptable substrates for diamine oxidase (DAO) and the novel phenacyl derivatives (2) are obtained in satisfactory preparative yield; no enantioselectivity is observed with (11) as an enzyme substrate.Remarkably, the triamines (9) and (13) are not oxidized and, moreover, (9) acts as a notable inhibitor for the DAO catalysed oxidation of (4) and (5).Kinetic evidence relevant to the mechanism of DAO action is presented, and is discussed in terms of a model for DAO-catalysed oxidation.
A NEW EFFICIENT SYNTHESIS OF β-AMINOKETONES VIA Δ4-ISOXAZOLINES.
Mancuso, Vincent,Hootele, Claude
, p. 5917 - 5918 (2007/10/02)
β-aminoketones are prepared in good yield by hydrogenolysis (Pd/C) of the N-O bond of Δ4-isoxazolines obtained by 1,3-dipolar cycloaddition of nitrones with alkynes.
Biosynthesis of Phenanthroindolizidine Alkaloids: Incorporation of 2-Pyrrolidin-2-ylacetophenone and Benzoylacetic Acid and Derivatives
Herbert, Richard B.,Jackson, Frederick B.,Nicolson, Ian T.
, p. 825 - 831 (2007/10/02)
2-Pyrrolidin-2-ylacetophenone (12) and its oxygenated derivatives, (13) and (14), bearing 14C and 3H labels are synthesized and are shown to be intact precursors for the phenanthroindolizidine alkaloid, tylophorinine (16), in Tylophora asthmatica; the three amines, singly labelled with tritium, are shown to be precursors for tylophorine (3) and tylophorinidine (17).Benzoylacetic acid (9) and p-hydroxybenzoylacetic acid (10), but not 4-hydroxy-3-methoxybenzoylacetic acid, are also precursors for tylophorinine (16).The results allow partial description of the biosynthetic pathways tophenanthroindolizidine alkaloids.A degradation is described which allowed the location of label in 2-pyrrolidin-2-ylacetophenone, derived from ornithine, to be established.
Phenanthroindolizidine and Related Alkaloids: Synthesis of Tylophorine, Septicine, and Deoxytylophorinine
Cragg, John E.,Herbert, Richard B.,Jackson, Frederick B.,Moody, Christopher J.,Nicolson, Ian T.
, p. 2477 - 2486 (2007/10/02)
Tylophorine (1) is synthesized in two ways.The first method begins with the synthesis of the amide-ester (7), which on reaction, successively, with triethyloxonium fluoroborate and sodium borohydride, gives the aminoester (8) selectively; hydrolysis and polyphosphoric acid-catalysed ring-closure of compound (9) gives the ketone (10) which yields tylophorine (1) on Clemmensen reduction.An alternative approach is by a biogenetically patterned sequence which involves condensation of (3,4-dimethoxybenzoyl)acetic acid (26) with 1-pyrroline (24) generated either in situ from putrescine by pea-seedling diamine oxidase or from ornithine by oxidation with N-bromosuccinimide; the product (16) condenses with 3,4-dimethoxyphenylacetaldehyde in benzene to give an enamine .This undergoes cyclisation and dehydration in methanol; sodium borohydride reduction then gives the alkaloid septicine (19) which, on oxidation with thallium(III) trifluoroacetate, yields tylophorine (1).Deoxytylophorinine (34) is made in an exactly analogous manner to the latter method for tylophorine.
