Articolul precedent |
Articolul urmator |
591 1 |
Ultima descărcare din IBN: 2020-11-30 11:36 |
SM ISO690:2012 GRINCO, Marina, GÎRBU, Vladilena, BARBA, Alic, GORINCIOI, Elena, UNGUR, Nikon. Convenient synthesis of methyl (8S,9R,13S,14R)-4,4,8,9,13-pentamethyl-20(10-9)-abeo-ent-isocopala-5(10),11(12)-dien-15β-oate. In: Physical Methods in Coordination and Supramolecular Chemistry, 8-9 octombrie 2015, Chişinău. Chisinau, Republic of Moldova: 2015, XVIII, p. 69. |
EXPORT metadate: Google Scholar Crossref CERIF DataCite Dublin Core |
Physical Methods in Coordination and Supramolecular Chemistry XVIII, 2015 |
|||||
Conferința ""Physical Methods in Coordination and Supramolecular Chemistry"" Chişinău, Moldova, 8-9 octombrie 2015 | |||||
|
|||||
Pag. 69-69 | |||||
|
|||||
Descarcă PDF | |||||
Rezumat | |||||
Methyl (8S,9R,13S,14R)-4,4,8,9,13-pentamethyl-20(109)-abeo-ent-isocopala5(10),11(12)-dien-15β-oate 1, an analog of natural highly ichthyotoxic1,2 verrucosins -A and -B, has been successfully synthesized, starting from the methyl ent-isocopalate 2, according to the Scheme 1.shemeThe stereochemical structure of compound 1 has been established by NMR spectroscopic data. Assignments of 1H and 13C signals in spectra are made on the basis of 1D: (1H, 13C, DEPT135o) and 2D: homo- (1H/1H COSY-45o, NOE) and heteronuclear (1H/13C HSQC and HMBC) experiments. The presence of two double bonds in the skeleton is ascertained by long-range C-H correlation experiments (HMBC). The assignment of the configuration of diterpenoid 1 was proposed on the basis of its NOE-spectra. NOE interactions between H-1eq/H3-9 and H3-9/H-7ax support the suggested (9R)-configuration of compound 1, while NOEs between H-1ax/H-6ax and H-6ax/H-14 are indicative for the (R) relative stereochemistry at C-14. 13S-Configuration of final methyl ether has been determined by the absence of NOEs between H3-16/H3-17 that has been additionally corroborated by weak NOEs between H-13/H315 and H3-15/H3-8 in the corresponding spectra. Since no evidence was found in the literature, concerning the preparation of verrucosine A and –B derivatives with the rearranged isocopalane diterpene skeleton, the present report paves the way for such type of potentially endowed with promising biological properties compounds. |
|||||
|