76103-58-7Relevant academic research and scientific papers
Biomimetic Approach toward the Total Synthesis of rac-2-(Acylmethylene)pyrrolidine Alkaloids
Shih, Yu-Chiao,Tsai, Pei-Hua,Hsu, Chia-Chun,Chang, Chih-Wei,Jhong, Yuandong,Chen, Yun-Chung,Chien, Tun-Cheng
, p. 6669 - 6678 (2015/10/06)
2-(Acylmethylene)pyrrolidine derivatives were synthesized via intermolecular decarbonylative Mannich reaction from various methyl ketones and 1-alkyl-1-pyrroliniums, generated in situ from 1-alkylprolines. This approach mimics the biosynthetic pathway and provides a direct access to a series of 2-(acylmethylene)pyrrolidine alkaloids, including hygrine, N-methylruspolinone, dehydrodarlinine, and ruspolinone.
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.
THE APPLICATION OF THE SULPHIDE CONTRACTION TO THE SYNTHESIS OF SOME SIMPLE PYRROLIDINE ALKALOIDS
Ghirlando, Rodolfo,Howard, Arthur S.,Katz, Ruth B.,Michael, Joseph P.
, p. 2879 - 2884 (2007/10/02)
The alkaloids (+/-)-hygrine, (+/-)-dehydrodarlinine, (+/-)-dehydrodarlingianine, and (+/-)-N-methylruspolinone have been synthesised by selective reduction of vinylogous amides formed by sulphide contraction of the salts prepared by reaction of N-methyl-2
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.
