55695-91-5Relevant academic research and scientific papers
Potent oligomerization and macrocyclization activity of the thioesterase domain of vicenistatin polyketide synthase
Kudo, Fumitaka,Asou, Yusaku,Watanabe, Moe,Kitayama, Takashi,Eguchi, Tadashi
supporting information; experimental part, p. 1843 - 1846 (2012/08/29)
The thioesterase domain of the polyketide synthase involved in the biosynthesis of the 20-membered macrolactam antibiotic vicenistatin (VinTE) was found to catalyze oligomerization and macrocyclization of ω-hydroxy fatty acid ethyl esters to afford 17-28-membered macrocyclic lactones. The ring sizes of the macrocycles appear to be limited to the more moderate sizes because of the space limitation of the active site of VinTE. It was also verified that the initially formed linear dimer is first released from the active site of VinTE and then is recognized again by VinTE prior to its transformation to the cyclic dimer.
Nematocidal thiocyanatins from a southern Australian marine sponge Oceanapia sp.
Capon, Robert J.,Skene, Colin,Liu, Edward Hsiang-Te,Lacey, Ernest,Gill, Jennifer H.,Heiland, Kirstin,Friedel, Thomas
, p. 1277 - 1282 (2007/10/03)
Investigations of a southern Australian marine sponge, Oceanapia sp., have yielded two new β methyl branched bisthiocyanates, thiocyanatins D 1 (3a) and D2 (3b), along with two new thiocarbamate thiocyanates, thiocyanatins E1 (4a) and E2 (4b). The new thiocyanatins belong to a rare class of bioactive marine metabolite previously only represented by thiocyanatins A-C (1, 2a/b). Structures were assigned on the basis of detailed spectroscopic analysis, with comparisons to the known bisthiocyanate thiocyanatin A (1) and synthetic model compounds (5-7). The thiocyanatins exhibit potent nematocidal activity, and preliminary structure-activity relationship investigations have confirmed key characteristics of the thiocyanatin pharmacophore.
The synthesis of (11R,12S)-lactobacillic acid and its enantiomer
Coxon, Geoffrey D.,Al-Dulayymi, Juma R.,Baird, Mark S.,Knobl, Stefan,Roberts, Evan,Minnikin, David E.
, p. 1211 - 1222 (2007/10/03)
(11R,12S)-Lactobacillic acid has been prepared from 2,3-O-isopropylidene-D-glyceraldehyde, in a sequence involving asymmetric cyclopropanation, and from cis-cyclopropane-1,2-dimethanol, using enzymatic desymmetrisation. The key step in the former route wa
Cuticular hydrocarbons and novel alkenediol diacetates from wheat stem sawfly (Cephus cinctus): Natural oxidation to pheromone components
Bartelt, Robert J.,Cosse, Allard A.,Petroski, Richard J.,Weaver, David K.
, p. 385 - 405 (2007/10/03)
The cuticular lipids of the wheat stem sawfly Cephus cinctus (Hymenoptera: Cephidae) were investigated as part of a chemical ecology project with this species. The major cuticular lipids were n-alkenes and n-alkanes. Alkenes were the most abundant and exhibited dramatic sexual dimorphism. (Z)-9-Tricosene accounted for about half of the total hydrocarbon in males but was nearly absent from females. The dominant alkenes in females were (Z)-9-pentacosene and (Z)-9-heptacosene. The alkane profiles were similar in both sexes, with n-tricosane being the most abundant, followed by n-pentacosane and n-heptacosane. In both sexes, there were minor amounts of alkanes and alkenes with other chain lengths and n-alkadienes of 29 and 31 carbons. In males, about one tenth of the surface lipids consisted of (Z)-9-alkene-1, ω-diol diacetates with 22-, 24-, and 26-carbon chains. The same compounds were also detected from females but in much smaller amounts. The structures of these novel diacetates were proven by synthesis. By analogy to methyl oleate, a well-studied food lipid, the alkenes and diacetates were expected to undergo slow oxidation in air to release specific aldehydes and other volatile products, and these were generally detected in volatiles collected from living sawflies. Atmospheric oxidation of the diacetates was also demonstrated in the absence of sawflies. One product from the diacetates, 9-acetyloxynonanal, was shown in other research to be particularly active electrophysiologically and was also attractive in the field. Aldehydes from the alkenes also showed strong electrophysiological activity. The concept of volatile pheromones originating from heavy, unsaturated cuticular lipids is discussed.
The synthesis of a 5-HETE photoaffinity ligand
Saha,Khanapure,Powell,Rokach
, p. 6313 - 6317 (2007/10/03)
The design and synthesis of a photoaffinity ligand 26, targeted at the 5h-dh, was accomplished. The synthesis was effected by two new synthetic routes which focus on the ω-hydroxy 5-HETE derivative 12 as a pivotal synthon. Preliminary results show ligand 26 to be an excellent substrate for the 5h-dh. (C) 2000 Elsevier Science Ltd.
Biosynthetic Studies of Marine Lipids. 5. The Biosynthesis of Long-Chain Branched Fatty Acids in Marine Sponges
Carballeira, Nestor,Thompson, Janice E.,Ayanoglu, Eser,Djerassi, Carl
, p. 2751 - 2756 (2007/10/02)
The very long chain branched fatty acids 25-methyl-5,9-hexacosadienoic (Δ5,9-iso-27:2)-and 24-methyl-5,9-hexacosadienoic (Δ5,9-anteiso-27:2) acids as well as the straight-chain 5,9-hexacosadienoic (Δ5,9-26:2) acid were shown to originate from the short-chain precursors 13-methyltetradecanoic (iso-15:0), 12-methyltetradecanoic (anteiso-15:0), and palmitic (n-16:0) acids, respectively, by means of 14C incorporation experiments in the marine sponge Jaspis stellifera.These results confirm that methyl branching does not occur after chain elongation.The unusual Δ5,9 unsaturation probably takes place after chain elongation of short branched or straight-chain fatty acids.
Synthesis and Spectra of Two Novel Catenanes
Logemann, Enno,Rissler, Klaus,Schill, Gottfried,Fritz, Hans
, p. 2245 - 2260 (2007/10/02)
In multi-step reaction sequences the precatenanes 23b, c are synthesised.After breaking the chemical bonds between the aromatic nuclei and the bridge head atoms of the double bridged system the -catenanes 25 b, c are obtained.The 13C NMR and mass spectra of the precatenanes and catenanes are discussed.
