共查询到20条相似文献,搜索用时 109 毫秒
1.
Daisuke Matsumura 《Tetrahedron letters》2009,50(26):3356-2160
The total synthesis of natural (+)-spiculoic acid A, a new cytotoxic marine natural product of polyketide origin, has been accomplished for the first time. The key step of the total synthesis was a stereoselective and high-yielding intramolecular Diels-Alder reaction of a highly functionalized (E,E,E)-2,7,9-dodecanal derivative for the construction of the core tetrahydroindan-2-one skeleton. 相似文献
2.
Kalesse M Chary KP Quitschalle M Burzlaff A Kasper C Scheper T 《Chemistry (Weinheim an der Bergstrasse, Germany)》2003,9(5):1129-1136
Callystatin A is a prominent member of a class of natural products which display promising growth inhibition of cancer cells in their biological profile. The challenging structure and the interesting biological activity of (-)-callystatin A fueled our interest in the synthesis of this marine natural product. We achieved the total synthesis using a highly convergent approach joining four subunits together with a Wittig olefination, a selective Heck reaction and an aldol reaction as the pivotal steps. The aldol reaction as one of the final transformations during the synthesis opens fast access to a variety of structural analogues and circumvents tedious protecting group manipulations. Here we report an improved synthesis utilizing a modified vinyl iodide which shortens the synthesis by two steps. Additionally, first biological results will be reported. 相似文献
3.
Atsushi Inoue 《Tetrahedron letters》2010,51(30):3966-4809
The first enantioselective total synthesis of aspermytin A, a new neurotrophic polyketide isolated from a cultured marine fungus of the genus Aspergillus sp., has been accomplished in 24 steps with an overall yield of 9.7% from S-(−)-citronellal. 相似文献
4.
A total synthesis of the cytotoxic polyketide marine natural product callystatin A is described. The route features chiral allenylmetal additions to construct the polypropionate C15-22 segment and an sp(2)-sp(3) Suzuki coupling to join the C1-C11 and C12-C22 subunits. 相似文献
5.
A total synthesis of the recently isolated polyketide natural product (±)-ambuic acid has been accomplished from the readily available Diels-Alder adduct of cyclopentadiene and 2-allyl-p-benzoquinone through a simple sequence with sound stereocontrol. 相似文献
6.
Daisuke MatsumuraToshimasa Takarabe Takumi TodaTakashi Hayamizu Kiyoto SawamuraKen-ichi Takao Kin-ichi Tadano 《Tetrahedron》2011,67(35):6730-6745
The total syntheses of both natural (+)-spiculoic acid A and (+)-zyggomphic acid, new cytotoxic marine natural products of polyketide origin, have been accomplished for the first time. These syntheses were achieved by the highly stereoselective and high-yielding intramolecular Diels-Alder reaction of a functionalized (E,E,E)-2,7,9-dodecanal derivative to construct the core tetrahydroindan-2-one skeleton. A stereocongener of (+)-spiculoic acid A, i.e., the (2R,5S,6R)-isomer, was also synthesized. The details of these total syntheses are described. 相似文献
7.
Enantioselective formal synthesis of macrolactone palmerolide A, a polyketide marine natural product, is described. Key strategies in the synthesis include the oxidative furan ring-opening of a chiral furyl carbinol for the installation of the 1,4-dienol core and a Jung nonaldol-aldol reaction for the dienamide core. 相似文献
8.
Prof. Dr. Hak Joong Kim Dr. Sei‐hyun Choi Byung‐sun Jeon Dr. Namho Kim Prof. Dr. Rongson Pongdee Dr. Qingquan Wu Prof. Dr. Hung‐wen Liu 《Angewandte Chemie (International ed. in English)》2014,53(49):13553-13557
Following the biosynthesis of polyketide backbones by polyketide synthases (PKSs), post‐PKS modifications result in a significantly elevated level of structural complexity that renders the chemical synthesis of these natural products challenging. We report herein a total synthesis of the widely used polyketide insecticide spinosyn A by exploiting the prowess of both chemical and enzymatic methods. As more polyketide biosynthetic pathways are characterized, this chemoenzymatic approach is expected to become readily adaptable to streamlining the synthesis of other complex polyketides with more elaborate post‐PKS modifications. 相似文献
9.
Dr. Robin Teufel Dr. Leonard Kaysser Matthew T. Villaume Dr. Stefan Diethelm Mary K. Carbullido Prof. Dr. Phil S. Baran Prof. Dr. Bradley S. Moore 《Angewandte Chemie (International ed. in English)》2014,53(41):11019-11022
The polycycles merochlorin A and B are complex halogenated meroterpenoid natural products with significant antibacterial activities and are produced by the marine bacterium Streptomyces sp. strain CNH‐189. Heterologously produced enzymes and chemical synthesis are employed herein to fully reconstitute the merochlorin biosynthesis in vitro. The interplay of a dedicated type III polyketide synthase, a prenyl diphosphate synthase, and an aromatic prenyltransferase allow formation of a highly unusual aromatic polyketide‐terpene hybrid intermediate which features an unprecedented branched sesquiterpene moiety from isosesquilavandulyl diphosphate. As supported by in vivo experiments, this precursor is furthermore chlorinated and cyclized to merochlorin A and isomeric merochlorin B by a single vanadium‐dependent haloperoxidase, thus completing the remarkably efficient pathway. 相似文献
10.
Stefan A. Ruider Tobias Sandmeier Prof. Dr. Erick M. Carreira 《Angewandte Chemie (International ed. in English)》2015,54(8):2378-2382
The first total synthesis of the marine polyketide (±)‐hippolachnin A has been achieved in nine linear steps and an overall yield of 9 %. Rapid access to the oxacyclobutapentalene core structure was secured by strategic application of an ene cyclization. 相似文献
11.
Wilson MC Nam SJ Gulder TA Kauffman CA Jensen PR Fenical W Moore BS 《Journal of the American Chemical Society》2011,133(6):1971-1977
Reported is the structure and biosynthesis of ansalactam A, an ansamycin class polyketide produced by an unusual modification of the polyketide pathway. This new metabolite, produced by a marine sediment-derived bacterium of the genus Streptomyces , possesses a novel spiro γ-lactam moiety and a distinctive isobutyryl polyketide fragment observed for the first time in this class of natural products. The structure of ansalactam A was defined by spectroscopic methods including X-ray crystallographic analysis. Biosynthetic studies with stable isotopes further led to the discovery of a new, branched chain polyketide synthase extender unit derived from (E)-4-methyl-2-pentenoic acid for polyketide assembly observed for the first time in this class of natural products. 相似文献
12.
Laksamee Jeanmard Panata Iawsipo Jiraporn Panprasert Vatcharin Rukachaisirikul Kwanruthai Tadpetch 《Tetrahedron》2018,74(34):4521-4529
The first and convergent total syntheses of polyketide natural products dechlorogreensporones A and D have been accomplished in 17 longest linear steps with 2.8% and 5.4% overall yields, respectively, starting from known methyl 2-(2-formyl-3,5-dihydroxyphenyl)acetate and commercially available R-(+)-propylene oxide and 1,2-epoxy-5-hexene. Our synthesis exploited key Mitsunobu esterification and (E)-selective ring-closing metathesis (RCM) to assemble the macrocycles as well as a Jacobsen hydrolytic kinetic resolution to install the stereogenic centers. Both synthetic compounds were found to display significant cytotoxic activity against seven human cancer cell lines with the IC50 ranges of 6.66–17.25?μM. 相似文献
13.
A new strategy for the synthesis of benzo[de][1,6]naphthyridine derivative 2,3,3a,4,5,6-hexahydroaaptamine, which involves the construction of the isoquinoline ring after elaboration of the quinoline moiety, is described. Since 2,3,3a,4,5,6-hexahydroaaptamine has been previously synthesized as a key intermediate en route to the marine alkaloid aaptamine, access to this compound represents a formal total synthesis of the natural product. 相似文献
14.
A new polyketide, untenolide A (1), has been isolated from an Okinawan marine sponge Plakortis species, and the structure was elucidated from spectroscopic data and X-ray analysis. Untenolide A (1) is a new polyketide possessing a fused-pentacyclic skeleton with two hexadecanyl chains. 相似文献
15.
B. Phaneendra ReddyT. Pandurangam J.S. YadavB.V. Subba Reddy 《Tetrahedron letters》2012,53(43):5749-5752
A highly stereoselective approach to the total synthesis of seimatopolide A and (2S,3R,5S)-(−)-2,3-dihydroxytetradecan-5-olide is described via a common polyketide precursor by means of Prins reaction and MacMillan aminoxylation sequence. 相似文献
16.
[reaction: see text] The conjugate addition of dithiols to bis-ynones generates a versatile masked 1,3,5-triketone platform. These functional units are useful intermediates for the synthesis of oxygen-containing heterocycles commonly found in polyketide natural products. The tetrahydropyranyl fragments of the marine macrolides Lyngbouilloside and Callipeltoside A have been synthesized with use of this methodology. 相似文献
17.
Yasuhiro Igarashi Daisuke Asano Kazuo Furihata Naoya Oku Satoshi Miyanaga Hiroaki Sakurai Ikuo Saiki 《Tetrahedron letters》2012,53(6):654-656
During the course of screening natural products for the inhibitors of tumor cell invasion, pterocidin, a linear polyketide with a δ-lactone terminus, was rediscovered from a Streptomyces strain of a marine sediment-origin. A series of J-based configuration analyses and NOESY analysis, coupled with chemical derivatization and chiral anisotropy analysis, established the absolute stereochemistry of five asymmetric centers in this compound. 相似文献
18.
We describe an expeditious enantioselective total synthesis of the acetylenic marine natural products (R)-strongylodiols A and B. Central to the strategy is the use of Zn(OTf)2, amine base, and N-methyl ephedrine to mediate the direct addition of a 1,3-diyne to two long-chain aliphatic aldehydes in useful selectivities and yields. 相似文献
19.
Veselin Nasufović Dr. Florian Küllmer Johanna Bößneck Dr. Hans-Martin Dahse Dr. Helmar Görls Dr. Peter Bellstedt Dr. Pierre Stallforth Prof. Dr. Hans-Dieter Arndt 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(45):11633-11642
The first total synthesis of the actin-stabilizing marine natural product geodiamolide H was achieved. Solid-phase based peptide assembly paired with scalable stereoselective syntheses of polyketide building blocks and an optimized esterification set the stage for investigating the key ring-closing metathesis. Geodiamolide H and synthetic analogues were characterized for their toxicity and for antiproliferative effects in cellulo, by characterising actin polymerization induction in vitro, and by docking on the F-actin target and property computation in silico, for a better understanding of structure-activity relationships (SAR). A non-natural analogue of geodiamolide H was discovered to be most potent in the series, suggesting significant potential for tool compound design. 相似文献
20.
Matthias Schmid Adriana S. Grossmann Peter Mayer Thomas Müller Thomas Magauer 《Tetrahedron》2019,75(24):3195-3215
We describe the evolution of a synthetic strategy for the construction of the marine polyketide salimabromide. Combining a bicyclo[3.1.0]hexan-2-one ring-expansion to build up a functionalized naphthalene and an unprecedented rearrangement/cyclization cascade, enabled synthesis of a dearomatized tricyclic subunit of the target compound. Alternatively, an intramolecular keteniminium [2 + 2]-cycloaddition and subsequent Baeyer–Villiger ring-expansion gave access to the sterically encumbered architecture of salimabromide. Sequential oxidation of the carbon framework finally enabled the total synthesis of this unusual natural product. 相似文献