77398-86-8Relevant academic research and scientific papers
Zum stereochemischen Verlauf der Biosynthese von 2-Oxo-pantolacton: Synthese von stereospezifisch indiziertem Pantolacton aus Aepfelsaeure
Wasmuth, Daniel,Arigoni, Duilio,Seebach, Dieter
, p. 344 - 352 (1982)
(+)-Pantolactone (13) has been synthesized from (-)-(S)-dimethyl malate (7) in 40percent yield in a short sequence involving double alkylation (7 -> 10 -> 11), selective hydrolysis (11 -> 12) and subsequent reduction (12 -> 13).Through variation of the alkylating agents and preparation of the two diastereomeric 3-ethyl-3-methyl malates 14 and 15 it was possible to show that the diastereoselectivity of the second alkylation step is brought about by preferential attack from the Re-face of the critical enolate (9, see also Scheme 1).This knowledge, in turn, has been exploited for the synthesis of a sample of pantolactone specifically enriched with 13C in its Si-methyl group.Analysis of the 13C-NMR. spectrum of this sample together with the results of biosynthetic experiments previously reported by Aberhart demonstrates that the biological hydroxymethylation of 2-oxoisovaleric acid (3) to 2-oxopantoic acid (4), an important step in the biosynthesis of pantothenic acid, takes place in a retention mode (cf.Scheme 2).
Synthesis of a chiral building block for the C6?C9fragment of epothilones
Valeev,Davletbaev,Talipov,Miftakhov
, p. 883 - 886 (2016/07/30)
A procedure has been developed for the synthesis of a new chiral building block for epothilone analogs starting from L-malic acid.
First total synthesis of the E- and Z-isomers of cytospolide-D
Kamal, Ahmed,Balakrishna, Moku,Reddy, Papagari Venkat,Rahim, Abdul
, p. 148 - 155 (2014/02/14)
A simple, convergent, and efficient approach for the total synthesis of the bioactive E- and Z-isomers of cytospolide-D is described. The key features of the synthetic strategy include stereoselective methylation, regioselective epoxide opening, olefin cr
Chiral pool synthesis of N-Cbz-cis-(3R,4R)-3-methylamino-4-methylpiperidine from L-Malic acid
Hao, Bao-Yu,Liu, Jin-Qiang,Zhang, Wei-Han,Chen, Xin-Zhi
, p. 1371 - 1377 (2013/07/28)
A new synthetic route to N-Cbz-cis-(3R,4R)-3-methylamino-4- methylpiperidine, key intermediate for CP- 690,550, was disclosed with L-malic acid as the chiral pool starting material. The title compound was obtained in 16 steps with a total yield of 26% and
The formal total synthesis of FR252921-An immunosuppressant
Yadav,Sengupta, Sandip
, p. 376 - 388 (2013/03/13)
The formal total synthesis of FR252921 is described. The key steps include the preparation of three fragments starting from 1,4-butanediol, (R)-malic acid, and prenol, respectively, followed by two consecutive peptide couplings of the three fragments. Other key steps involve an allene-type rearrangement or enyne isomerization to install the triene moiety, a Seebach methylation, a Julia olefination to construct the trisubstituted diene unit, and an enzymatic resolution strategy to generate the C-18 stereocenter.
The stereocontrolled total synthesis of spirastrellolide A methyl ester. Expedient construction of the key fragments
Paterson, Ian,Anderson, Edward A.,Dalby, Stephen M.,Lim, Jong Ho,Maltas, Philip,Loiseleur, Olivier,Genovino, Julien,Moessner, Christian
supporting information; scheme or table, p. 5861 - 5872 (2012/08/28)
Due to a combination of their promising anticancer properties, limited supply from the marine sponge source and their unprecedented molecular architecture, spirastrellolides represent attractive and challenging synthetic targets. A modular strategy for the synthesis of spirastrellolide A methyl ester, which allowed for the initial stereochemical uncertainties in the assigned structure was adopted, based on the envisaged sequential coupling of a series of suitably functionalised fragments; in this first paper, full details of the synthesis of these fragments are described. The pivotal C26-C40 DEF bis-spiroacetal was assembled by a double Sharpless asymmetric dihydroxylation/acetalisation cascade process on a linear diene intermediate, configuring the C31 and C35 acetal centres under suitably mild acidic conditions. A C1-C16 alkyne fragment was constructed by application of an oxy-Michael reaction to introduce the A-ring tetrahydropyran, a Sakurai allylation to install the C9 hydroxyl, and a 1,4-syn boron aldol/directed reduction sequence to establish the C11 and C13 stereocentres. Two different coupling strategies were investigated to elaborate the C26-C40 DEF fragment, involving either a C17-C25 sulfone or a C17-C24 vinyl iodide, each of which was prepared using an Evans glycolate aldol reaction. The remaining C43-C47 vinyl stannane fragment required for introduction of the unsaturated side chain was prepared from (R)-malic acid.
The sex pheromone of the wasp spider Argiope bruennichi
Chinta, Satya P.,Goller, Stephan,Lux, Julia,Funke, Sebastian,Uhl, Gabriele,Schulz, Stefan
supporting information; experimental part, p. 2033 - 2036 (2010/06/20)
(Figure Presented) Wasp spider looking for a mate: Female wasp spiders (see picture) use trimethyl methylcitrate as a volatile cue to attract males. The experiments were performed on a sunny meadow, showing for the first time that spider traps can be used to trap spiders in the field (photo: Helen Sandford).
Total synthesis of berkelic acid
Snaddon, Thomas N.,Buchgraber, Philipp,Schulthoff, Saskia,Wirtz, Conny,Mynott, Richard,Fuerstner, Alois
supporting information; experimental part, p. 12133 - 12140 (2011/02/25)
A productive total synthesis of both enantiomers of berkelic acid (1) is outlined that takes the structure revision of this bioactive fungal metabolite previously proposed by our group into account. The successful route relies on a fully optimized triple-deprotection/1,4-addition/spiroacetalization cascade reaction sequence, which delivers the tetracyclic core 32 of the target as a single isomer in excellent yield. The required cyclization precursor 31 is assembled from the polysubstituted benzaldehyde derivative 20 and methyl ketone 25 by an aldol condensation, in which the acetyl residue in 20 transforms from a passive protecting group into an active participant. Access to fragment 25 takes advantage of the Collum-Godenschwager variant of the ester enolate Claisen rearrangement, which clearly surpasses the classical Ireland-Claisen procedure in terms of diastereoselectivity. Although it is possible to elaborate 32 into the target without any additional manipulations of protecting groups, a short detour consisting in the conversion of the phenolic -OH into the corresponding TBS-ether is beneficial. It tempers the sensitivity of the compound toward oxidation and hence improves the efficiency and reliability of the final stages. Orthogonal ester groups for the benzoate and the aliphatic carboxylate terminus of the side chain secure an efficient liberation of free berkelic acid in the final step of the route. Queue up: Three deprotection and three bond-forming reactions, all of which are effected just by a trace of HCl, zip an easily attained enone to the polycyclic core of berkelic acid in diastereomerically pure form and essentially quantitative yield. This cascade process paves the way to a concise and effective total synthesis of this alleged metalloproteinase-3 inhibitor and cytotoxic metabolite derived from an extremophilic fungus.
Stereoselective synthesis of (3R,4S,5S,9S)-3,5,9-trihydroxy-4-methylundecanoic acid δ-lactone
Yadav,Reddy, P. Murali Krishna,Reddy, P. Venkatram
, p. 1037 - 1039 (2008/02/05)
A stereoselective synthesis of the pentaketide lactone (3R,4S,5S,9S)-3,5,9-trihydroxy-4-methylundecanoic acid δ-lactone has been achieved.
Total synthesis of 6-epiprelactone-V via a syn-selective oxygen tethered intramolecular Michael reaction
Chandrasekhar,Rambabu,Prakash, S. Jaya
, p. 1213 - 1215 (2007/10/03)
The intramolecular protective group (benzylidene acetal) assisted syn-1,3-diol synthesis has been efficiently utilized in a short synthesis of 6-epiprelactone-V starting from (S)-malic acid.
