10407-70-2Relevant articles and documents
STEREOSELECTIVE SYNTHESIS OF (+/-)-INTEGERRINECIC ACID
Narasaka, Koichi,Uchimaru, Tadafumi
, p. 57 - 58 (1982)
A synthesis of (+/-)-integerrinecic acid, an acid part of 12-membered bislactonic pyrrolizidine alkaloid, has been achieved stereoselectively starting from 2-methyl-2-cyclopentanone.
Pyrrolizidine Alkaloid Biosynthesis. Synthesis of 3H-Labelled Trachelanthamidine and Isoretronecanol and their Incorporation into Three Pyrrolizidine Bases (Necines)
Kunec, Ellen K.,Robins, David J.
, p. 1437 - 1441 (2007/10/02)
(+/-)-Isoretronecanol (22) and (+/-)-trachelanthamidine (24) were prepared by 1,3-dipolar cycloaddition of N-formylproline with ethyl propiolate followed by reduction steps.These 3H-labelled 1-hydroxymethylpyrrolizidines together with putrescine were fed to Senecio isatideus which produces retrorsine (1); S. pleistocephalus which yields rosmarinine (8); and Cynoglossum officinale which affords echinatine (5).The double labelling experiments demonstrated that isoretronecanol is incorporated much more efficiently into rosmarinine than into retrorsine or echinatine, whereas trachelanthamidine is a much more efficient precursor for retrorsine and echinatine.Base hydrolysis of retrorsine and echinatine labelled with trachelanthamidine and of rosmarinine labelled with isoretronecanol established that most of the 3H-label was in the base portions, retronecine (2), heliotridine (6), and rosmarinecine (9), respectively.Further degradation of retronecine and rosmarinecine showed that most of the radioactivity was confined to the β-alanine (4) portion.The biosynthetic pathways to isoretronecanol and trachelanthamidine apparently diverge prior to the formation of these 1-hydroxymethylpyrrolizidines, probably during the cyclisation of an immonium ion (14) to form the 1-formylpyrrolizidines (15) and (17).
Total Synthesis of a Macrocyclic Pyrrolizidine Alkaloid, (+/-)-Integerrimine, Utilizing an Activable Protecting Group
Narasaka, Koichi,Sakakura, Toshiyasu,Uchimaru, Tadafumi,Guedin-Vuong, Denis
, p. 2954 - 2961 (2007/10/02)
A new esterification reaction has been developed utilizing a (methylthio)methyl (MTM) group as an activable protecting group of carbocyclic acid.A total synthesis of a 12-membered pyrrolizidine alkaloid, (+/-)-integerrimine (1), has been achieved by applying the above method to formation of the macrocyclic bislactone skeleton.The acid anhydride (16b) of the integerrinecic acid derivative was coupled with lithium alkoxide of retronecine silyl ether (5b) in the presence of DMAP to afford the α,β-unsaturated ester.Oxidation of the MTM group afforded an active (methylsulfonyl)methyl ester (28b), which cyclized to give the macrocyclic bislactone 29.
Necic Acid Synthons. Part 1. Total Synthesis of Integerrinecic Acid
Drewes, Siegfried E.,Emslie, Neville D.
, p. 2079 - 2084 (2007/10/02)
The synthesis of racemic integerrinecic acid from ethyl acrylate is described.Overall, five steps are involved.A key synthon in the synthesis, ethyl (2Z)-2-bromomethylbut-2-enoate, can undergo either allylic substitution or substitution with rearrangement, and opens the way for a 'general' synthesis toa range of necic acids.
The Synthesis of Racemic trans-6-Hydroxy-5-methyl-2-heptene-3,6-dicarboxylic Acid (Integerrinecic Acid)
Pastewka, Ulrich,Wiedenfeld, Helmut,Roeder, Erhard
, p. 846 - 850 (2007/10/02)
The synthesis of the title compound 9 is described.The structures of the isolated intermediates of the synthesis were elucidated by IR, (1)H-NMR and mass spectroscopy.
