248251-87-8Relevant academic research and scientific papers
A concise and enantioselective synthesis of a C-6 O-acyl side chain equivalent of zaragozic acid A
Nakamura, Seiichi,Inagaki, Jun,Kitaguchi, Junichi,Tatani, Kazuya,Hashimoto, Shunichi
, p. 1330 - 1333 (1999)
An optically pure C-6 O-acyl side chain equivalent of zaragozic acid A, (2E,4S,6S)-4,6-dimethyl-2-octenoic acid, which features a 1,3-syn-dimethyl- substituted carbon chain, has been readily synthesized from (S)-2- methylbutanal using a combination of the Evans aldol reaction and the Ireland deoxygenation method.
Total synthesis and structural elucidation of ent-micropyrone and (+)-ascosalipyrone
Gregg, Claire,Perkins, Michael V.
, p. 6547 - 6553 (2012/09/08)
The total synthesis of 6-[(1S,3S)-1,3-dimethyl-2-oxopentyl]-4-hydroxy-3,5- dimethyl-2H-pyran-2-one (22), the enantiomer of the natural product micropyrone (1), was achieved in 9 linear steps (10% overall yield), from Evans auxiliary (R)-12 with key coupli
Total synthesis of the potent antitumor polyketide (-)-callystatin A
Dias, Luiz C.,Meira, Paulo R. R.
, p. 4762 - 4773 (2007/10/03)
A highly convergent and efficient total synthesis of the potent antitumor polyketide (-)-callystatin A is described. The synthesis required 19 steps from N-propionyl oxazolidinone 23 and produced the desired product in 3.5% overall yield.
Precursor-Directed Biosynthesis: Stereospecificity for Branched-Chain Diketides of the β-Ketoacyl-ACP Synthase Domain 2 of 6-Deoxyerythronolide B Synthase
Kinoshita, Kenji,Khosla, Chaitan,Cane, David E.
, p. 3889 - 3907 (2007/10/03)
Modular polyketide synthases such as 6-deoxyerythronolide B synthase (DEBS) catalyze the biosynthesis of structurally complex natural products. Streptomyces coelicolor CH999/pJRJ2 harbors a plasmid encoding DEBS(KS1 0), a mutant form of 6-deoxyerythronolide B synthase that is blocked in the formation of 6-deoxyerythronolide B (1, 6-dEB) due to a mutation in the active site of the ketosynthase (KS1) domain that normally catalyzes the first polyketide chain-elongation step of 6-dEB biosynthesis. Administration of (2S,3R,4S)- and (2S,3R,4R)-3-hydroxy-2,4-dimethylhexanoic acid N-acetylcysteamine (SNAC) thioesters (= S-[2-(acetylamino)ethyl] (2S,3R,4S)- and (2S,3R,4R)-3-hydroxy-2,4-dimethylhexanethioates) 3 and 4 in separate experiments to cultures of Streptomyces coelicolor CH999/pJRJ2 led to production of the corresponding (14S)- and (14R)-14-methyl analogues of 6-dEB, 10 and 11, respectively. Unexpectedly, when a 3:2 mixture of 4 and 3 was fed under the same conditions, exclusively branched-chain macrolactone 11 was isolated. In similar experiments, feeding of 3 and 4 to S. coelicolor CH999/pCK16, an engineered strain harboring DEBS1 + TE(KS10), resulted in formation of the branched-chain triketide lactones 13 and 14, while feeding of the 3:2 mixture of 4 and 3 gave exclusively 14. The biochemical basis for this stereochemical discrimination was established by using purified DEBS module 2 + TE to determine the steady-state kinetic parameters for 3 and 4, with the kcat/KM for 4 shown to be sevenfold greater than that of 3.
Synthesis of C13-C22 fragment of the marine sponge polyketide callystatin A
Dias, Luiz C.,Meira, Paulo R.R.
, p. 185 - 187 (2007/10/03)
We wish to report here our initial efforts towards the total synthesis of callystatin A, describing the synthesis of the C13-C22 fragment. This asymmetric approach uses an efficient syn-aldol reaction, and a diastereoselective epoxidation of an allylic al
