90344-49-3Relevant articles and documents
Progress toward the total synthesis of mirabalin isomers
Echeverria, Pierre-Georges,Pons, Amandine,Prévost, Sébastien,Férard, Charlène,Cornil, Johan,Guérinot, Amandine,Cossy, Janine,Phansavath, Phannarath,Ratovelomanana-Vidal, Virginie
, p. 44 - 68 (2019/04/17)
Key fragments of the cytotoxic marine macrolide mirabalin have been synthesized, by using a flexible strategy based on asymmetric reductions to control the hydroxy- and carbamate-bearing stereocenters. In particular, ruthenium or rhodium-mediated asymmetric hydrogenation and transfer hydrogenation were used in combination with a dynamic kinetic resolution to control two contiguous stereocenters in a single step.
Mechanism and stereospecificity of a fully saturating polyketide synthase module: Nanchangmycin synthase module 2 and its dehydratase domain
Guo, Xun,Liu, Tiangang,Valenzano, Chiara R.,Deng, Zixin,Cane, David E.
, p. 14694 - 14696 (2011/01/07)
Recombinant nanchangmycin synthase module 2 (NANS module 2), with the thioesterase domain from the 6-deoxyerythronolide B synthase (DEBS TE) appended to the C-terminus, was cloned and expressed in Escherichia coli. Incubation of NANS module 2+TE with (±)-2-methyl-3-keto-butyryl-N-acetylcysteamine thioester (1), the SNAC analog of the natural ACP-bound substrate, with methylmalonyl-CoA (MM-CoA) in the absence of NADPH gave 3,5,6-trimethyl-4- hydroxypyrone (2), identified by direct comparison with synthetic 2 by radio-TLC-phosphorimaging and LC-ESI(+)-MS-MS. The reaction showed k cat 0.5 ± 0.1 min-1 and Km(1) 19 ± 5 mM at 0.5 mM MM-CoA and kcat(app) 0.26 ± 0.02 min-1 and Km(MM-CoA) 0.11 ± 0.02 mM at 8 mM 1. Incubation in the presence of NADPH generated the fully saturated triketide chain elongation product as a 5:3 mixture of (2S,4R)-2,4-dimethyl-5-ketohexanoic acid (3a) and the diastereomeric (2S,4S)-3b. The structure and stereochemistry of each product was established by comparison with synthetic 3a and 3b by a combination of radio-TLC-phosphorimaging and LC-ESI(-)-MS-MS, as well as chiral capillary GC-MS analysis of the corresponding methyl esters 3a-Me and 3b-Me. The recombinant dehydratase domain from NANS module 2, NANS DH2, was shown to catalyze the formation of an (E)-double bond by syn-dehydration of the ACP-bound substrate anti-(2R,3R,4S,5R)-2,4-dimethyl-3,5-dihydroxyheptanoyl-ACP6 (4), generated in situ by incubation of (2S,3R)-2-methyl-3-hydroxypentanoyl-SNAC (5), methylmalonyl-CoA, and NADPH with the recombinant [KS6][AT6] didomain and ACP6 from DEBS module 6 along with the ketoreductase from the tylactone synthase module 1 (TYLS KR1). These results also indirectly establish the stereochemistry of the reactions catalyzed by the KR and enoylreductase (ER) domains of NANS module 2.
An approach to an asymmetric synthesis of stemofoline
Thomas, Eric J.,Vickers, Clare F.
scheme or table, p. 970 - 979 (2009/09/30)
A stereoselective Mannich reaction between an (S)-tert-butylsulfinimine and methyl (S)-4-benzyloxy-3-methylbutanoate followed by treatment with acid and N-protection was used to prepare methyl (2R,3S)-2-[(S)-2-benzyloxy-1-methylethyl]-3-tert-butoxycarbony
Stereocontrolled and convergent total synthesis of amphidinolide T3
Deng, Li-Sheng,Huang, Xiao-Ping,Zhao, Gang
, p. 4625 - 4635 (2007/10/03)
Stereocontrolled and convergent total synthesis of amphidinolide T3 has been described. A retrosynthetic scheme was constructed that led to the recognition of readily available and enantiomerically related compounds as starting materials for the total synthesis of amphidinolide T3. Thus, the two key building blocks 6 and 7 were defined as subtargets and synthesized in optically active forms. The C1-C12 fragment 6 was derived from commercially available D-glutamic acid or its synthetically equivalent (R)-5- hydroxymethyltetrahydrofuran-2-one 16 as starting material involving highly diastereoselective asymmetric allylation as a key step. The C13-C21 fragment 7 was efficiently synthesized in high yield through the dithiane coupling of the segment 10 and iodide 11, followed by subsequent deprotection and Petasis olefination. Eventually, assembly of the fragment aldehyde 6 and dithiane 7 along with C-C bond formation, a two-step oxidation-reduction sequence, selective macrolactonization, and functional transformation furnished the convergent total and formal synthesis of amphidinolide T3 and T4, and this approach also provides a flexible and practical synthesis of amphidinolide T macrolides.
Silanediol inhibitors of angiotensin-converting enzyme. Synthesis and evaluation of four diastereomers of Phe[Si]Ala dipeptide analogues
Kim, Jaeseung,Hewitt, Gregory,Carroll, Patrick,Sieburth, Scott Mc. N.
, p. 5781 - 5789 (2007/10/03)
Four stereoisomers of a Phe-Ala silanediol dipeptide mimic have been evaluated as inhibitors of angiotensin-converting enzyme (ACE) and compared to ketone-based inhibitors reported by Almquist et al. One stereogenic center of the isomers was derived from
Silanediol peptidomimetics. Evaluation of four diastereomeric ACE inhibitors
Kim, Jaeseung,Sieburth, Scott McN.
, p. 2853 - 2856 (2007/10/03)
Four diastereomers of a Phe-Ala peptide mimic incorporating a central silanediol group have been individually prepared and tested as inhibitors of angiotensin-converting enzyme (ACE). Three of the silanediols exhibit levels of inhibition that are similar
Synthetic studies on borrelidin: enantioselective synthesis of the C1-C12 fragment.
Vong, Binh G,Abraham, Sunny,Xiang, Alan X,Theodorakis, Emmanuel A
, p. 1617 - 1620 (2007/10/03)
[structure: see text] An efficient, enantioselective synthesis of the C1-C12 fragment 2 of borrelidin is presented. Construction of the "skipped" polymethylene chain of 2 was accomplished by iteration of Myers' alkylation, while formation of the C3 stereocenter was achieved by Roush's asymmetric allylboration methodology.
Chiral synthesis of C-carboxyalkyl dipeptide inhibitors of stromelysin- 1 (MMP-3)
Ponpipom, Mitree M.,Hagmann, William K.
, p. 6749 - 6758 (2007/10/03)
Enantioselective alkylation of chiral amide enolates derived from L- prolinol with β-branched chiral iodides afforded good yields of hydroxy amide adducts, which were elaborated in four steps to give C-carboxyalkyl dipeptide inhibitors of stromelysin-1 (MMP-3).
Approach to the Synthesis of Enantiomerically Pure Chatancin. I. Synthesis of (1R,2S,6S,7R,8S,3'S)-2-(4'-Benzyloxy-3'-methylbutoyl)-7-hydroxy-8-isopropyl-1-methylbicyclodecan-4-on
Aichberger, W. D.,Aigner, J.,Goessinger, E.,Gruber, K.,Menz, G.
, p. 991 - 1010 (2007/10/02)
Our first target on the way towards the synthesis of enantiomerically pure chatancin is the preparation of the title compound.The cycloadduct of 5,5-dimethoxy-1,2,3,4-tetrachlorocyclopentadiene and thymoquinone is stereo- and regioselectively reduced to t
Total Synthesis of (+)-Latrunculin A, an Ichthyotoxic Metabolite of the Sponge Latrunculia magnifica, and Its C-15 Epimer
White, James D.,Kawasaki, Motoji
, p. 5292 - 5300 (2007/10/02)
Latrunculin A (1), an ichthyotoxic metabolite of the sponge Latrunculia magnifica with potent inhibitory action on microfilament-mediated processes involved in cell division, was synthesized via a convergent approach.Construction of a major segment of the latrunculin backbone was accomplished by means of a three-component coupling of aldehyde 24, β-keto ester 27, and phosphonium salt 26, which established the conjugated E,Z-diene moiety of 31.The thiazolidinone subunit of 1 was elaborated in the form of 39 from L-cysteine and was linked to 35 without nitrogen protection.Final lactonization of 47 was carried out using the Mitsunobu protocol.A parallel sequence employing the epimeric seco acid 48 produced 15-epilatrunculin A.
