共查询到20条相似文献,搜索用时 78 毫秒
1.
Sawamura K Yoshida K Suzuki A Motozaki T Kozawa I Hayamizu T Munakata R Takao K Tadano K 《The Journal of organic chemistry》2007,72(16):6143-6148
Total syntheses of the antimicrobial tricyclic 16-membered macrolides, (+)-tubelactomicin B, (+)-tubelactomicin D, and (+)-tubelactomicin E, have been accomplished for the first time with common synthetic approaches. These total syntheses established the relative and absolute configurations of the three tubelactomicins, for which planar structures had solely been reported. The total synthesis of (+)-tubelactomicin D included a newly developed stereoselective intramolecular Diels-Alder reaction for constructing the highly functionalized octahydronaphthalene substructures. 相似文献
2.
Matthew R. Aronoff 《Tetrahedron letters》2010,51(49):6375-6377
The first asymmetric total syntheses of the antiviral natural products (+)-sattabacin and (+)-4-hydroxysattabacin are reported. Both total syntheses are remarkably concise and were completed without the use of protecting groups. These syntheses allowed the unambiguous assignment of the absolute configuration of both natural products. The syntheses of these natural products, which exhibit marked antiviral activity, are readily amenable to the preparation of structural analogs and progress in this regard is also reported. 相似文献
3.
The total syntheses of (-)-magellanine, (+)-magellaninone, and (+)-paniculatine were completed from diethyl l-tartrate via the common intermediate in a stereoselective manner. The crucial steps in these syntheses involved two intramolecular Pauson-Khand reactions of enynes: the first Pauson-Khand reaction constructed the bicyclo[4.3.0] carbon framework, the corresponding A and B rings of these alkaloids in a highly stereoselective manner, whereas the second Pauson-Khand reaction stereoselectively produced the bicyclo[3.3.0]skeleton, which could be converted into the C and D rings of the target natural products. 相似文献
4.
Mauricio Navarro Villalobos Susan Jeong Cristy Lindberg Benson Steven M. Zeman Catherine McCarty Matthew M. Weiss Analee Salcedo Jonathan Jenkins 《Tetrahedron》2009,65(39):8091-1520
The first total syntheses of (−)-syringolide 3, (+)-syributin 3 and their unnatural enantiomers (+)-syringolide 3 and (−)-syributin 3 using a common intermediate as starting material are described. In addition, total syntheses of (−)- and (+)-syributins 1 and 2 were accomplished by means of the same methodology. 相似文献
5.
Synthesis of optically active natural carotenoids and structurally related compounds. III. Synthesis of (+)-abscisic acid, (?)-xanthoxin, (?)-loliolide, (?)-actinidiolide, and (?)-dihydroactinidiolide The syntheses of (+)-abscisic acid ( 1 ), (?)-xanthoxin ( 2 ), (?)-loliolide ( 3 ), (?)-actinidiolide ( 4 ), and of (?)-dihydroactinidiolide ( 5 ) from one common starting material are reported. The syntheses yield also some enantiomeric or diastereomeric analogues. 相似文献
6.
《Tetrahedron》2003,59(6):857-864
The stereoselective syntheses of the naturally occurring δ-lactones (+)-tanikolide and (−)-malyngolide as well as of the unnatural (+)-enantiomer of the latter are described. Key steps in each of these syntheses were stereoselective additions of organometallic reagents to α-oxygenated ketones and olefin ring-closing metatheses. 相似文献
7.
Christian Gnamm Dipl.‐Chem. Kerstin Brödner Caroline M. Krauter Günter Helmchen Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(40):10514-10532
A method for the stereoselective synthesis of 2,6‐disubstituted piperidines has been developed that is based on the use of an intramolecular iridium‐catalyzed allylic substitution as a configurational switch. The procedure allows the preparation of 2‐vinylpiperidines with enantiomeric excesses (ee) of greater than 99 %. As applications, total syntheses of piperidine alkaloids have been elaborated, most often by using Ru‐catalyzed cross‐metatheses as a key step for introduction of a side chain. Asymmetric total syntheses of the prosopis alkaloids (+)‐prosopinine, (+)‐prosophylline, (+)‐prosopine, and of the dendrobate alkaloid (+)‐241D and its C6 epimer are described. 相似文献
8.
Short and Divergent Total Synthesis of (+)‐Machaeriol B, (+)‐Machaeriol D, (+)‐Δ8‐THC,and Analogues
下载免费PDF全文
![点击此处可从《Angewandte Chemie (International ed. in English)》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Felix Klotter Prof. Dr. Armido Studer 《Angewandte Chemie (International ed. in English)》2015,54(29):8547-8550
Short and highly efficient stereoselective syntheses provide machaeriols and cannabinoids in a divergent approach starting from a common precursor, commercially available (S)‐perillic acid. Key features of the novel strategy are a stereospecific palladium‐catalyzed decarboxylative arylation and a one‐pot sequence comprising a stereoselective hydroboration followed by oxidation or reduction of the corresponding intermediary boranes. The divergent approach is convincingly demonstrated by the five‐step syntheses of (+)‐machaeriol B, (+)‐machaeriol D, and related analogues, and the four‐step synthesis of (+)‐Δ8‐THC and an analogue. 相似文献
9.
Total syntheses of (+)-7-epi-goniofufurone, (+)-goniopypyrone and (+)-goniofufurone have been achieved from an advanced common precursor formed from D-(+)-mannitol by changing the carbinol protection profile. 相似文献
10.
The first enantioselective total syntheses of indole alkaloids of the condylocarpine type are reported. (+)-Condylocarpine, (+)-isocondylocarpine, and (+)-tubotaiwine were prepared in high enantiomeric purity (er > 99:1) from (1S,5R)-hexahydro-1,5-methano-1H-azocino[4,3-b]indole-12-one 7b by way of five or six isolated intermediates. 相似文献
11.
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
12.
Concise asymmetric total syntheses of the fungal metabolites (-)-stephacidin A, (+)-stephacidin B, and (+)-notoamide B are described. Key features of these total syntheses include (1) a facile synthesis of (R)-allyl proline methyl ester, (2) a revised route toward the pyranoindole ring system, (3) a novel cross-metathesis strategy for the introduction of important functional groups, and (4) an SN2' cyclization to form the [2.2.2] bridged bicyclic ring system. Furthermore, our synthesis has taken advantage of microwave heating to shorten reaction times as well as increase yields for the preparation of vital intermediates. 相似文献
13.
Design, synthesis, and evaluation of carbamate-substituted analogues of (+)-discodermolide 总被引:1,自引:0,他引:1
Smith AB Freeze BS Lamarche MJ Hirose T Brouard I Rucker PV Xian M Sundermann KF Shaw SJ Burlingame MA Horwitz SB Myles DC 《Organic letters》2005,7(2):311-314
[Structure: see text] The design, syntheses, and biological evaluation of 22 totally synthetic analogues of the potent microtubule-stabilizing agent (+)-discodermolide (1) have been achieved. Structure-activity relationships of the C(19) carbamate were defined, exploiting two synthetically simplified scaffolds, as well as the parent (+)-discodermolide framework. 相似文献
14.
Chuan He Jun Xuan Peirong Rao Pei‐Pei Xie Xin Hong Xufeng Lin Hanfeng Ding 《Angewandte Chemie (International ed. in English)》2019,58(15):5100-5104
A concise and divergent approach for the total syntheses of four cembrane diterpenoids, namely (+)‐sarcophytin, (+)‐chatancin, (?)‐3‐oxochatancin, and (?)‐pavidolide B, has been developed, and it also led to the structural revision of (?)‐isosarcophytin. The key steps of the strategy feature a double Mukaiyama Michael addition/elimination, a Helquist annulation, two substrate‐controlled facial‐selective hydrations, and a pinacol rearrangement. The described syntheses not only achieved these natural products in an efficient manner, but also provided insight into the biosynthetic relationship between the two different skeletons. 相似文献
15.
Chuan He Jun Xuan Peirong Rao Pei‐Pei Xie Xin Hong Xufeng Lin Hanfeng Ding 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(15):5154-5158
A concise and divergent approach for the total syntheses of four cembrane diterpenoids, namely (+)‐sarcophytin, (+)‐chatancin, (?)‐3‐oxochatancin, and (?)‐pavidolide B, has been developed, and it also led to the structural revision of (?)‐isosarcophytin. The key steps of the strategy feature a double Mukaiyama Michael addition/elimination, a Helquist annulation, two substrate‐controlled facial‐selective hydrations, and a pinacol rearrangement. The described syntheses not only achieved these natural products in an efficient manner, but also provided insight into the biosynthetic relationship between the two different skeletons. 相似文献
16.
Germain AR Bruggemeyer DM Zhu J Genet C O'Brien P Porco JA 《The Journal of organic chemistry》2011,76(8):2577-2584
Enantioselective syntheses of the azaphilone natural products (+)-sclerotiorin and (+)-8-O-methylsclerotiorinamine that possess the natural R-configuration at the quaternary center are reported. The syntheses were accomplished using copper-mediated asymmetric dearomatization employing bis-μ-oxo copper complexes prepared from readily available (+)-sparteine surrogates. Of note, site-selective O-methylation of a vinylogous pyridone was used to access the isoquinolin-6(7H)-one core of (+)-8-O-methylsclerotiorinamine. 相似文献
17.
[structures: see text] The total syntheses of the amaryllidaceae alkaloids haemanthidine, pretazettine, and tazettine as optically pure enantiomers are reported. Using D-mannose as the starting material, the critical relative stereochemical relationships are established with an intramolecular nitrone-alkene cycloaddition reaction. The synthetic route leads successively to (-)-haemanthidine and then to (+)-pretazettine and (+)-tazettine, taking advantage of the well-established complex relationships among these three alkaloids. 相似文献
18.
Curti C Zanardi F Battistini L Sartori A Rassu G Pinna L Casiraghi G 《The Journal of organic chemistry》2006,71(22):8552-8558
Highly direct, modular syntheses of several natural 8,4'-oxyneolignans [(-)-1, (+)-1, (-)-2, and (-)-3] and some related variants [(-)-26, (+)-26, (+)-27, and (-)-28] are reported. Utilizing (S)- or (R)-methyl lactate as the chiral sources, two complementary syn- or anti-oriented routes were designed, encompassing nine and five steps, which were carried out to deliver the targets in an enantiomerically pure form. The embodiment of the two independent aryl and aryloxy moieties onto the lactate frame was performed according to a diversity-oriented protocol from the common precursors, aldehydes 6 and ent-6 for the syn-oriented routes and mesyl esters 19 and ent-19 for the anti-oriented routes. These syntheses set the stage for the generation of a wide and diverse repertoire of 8,4'-oxyneolignan compounds and the broad biological interrogation of its members. 相似文献
19.
[structure: see text] The design, total synthesis, and biological evaluation of two C13-C14-cyclopropyl analogues [(+)-1 and (+)-2] of (+)-discodermolide have been achieved. Key features of the syntheses include highly stereoselective, hydroxyl-directed cyclopropanations of vinyl iodides and higher order cuprate-mediated cross-coupling reactions between cyclopropyl iodides and alkyl iodides. Biological evaluation revealed that neither orientation of the cyclopropyl methylene completely substitutes for the C14 methyl found in (+)-discodermolide (3). 相似文献
20.
Recent progress of total syntheses in our laboratory has been described along with our background and methodologies. The target bioactive polyketides are classified into three categories according to their structures: (i) lactone-fused polycyclic compounds [(+)-cochleamycin A, (+)-tubelactomicin A, and (-)-tetrodecamycin], (ii) aromatic compounds [(-)-tetracycline, (-)-BE-54238B, lymphostin, and (-)-lagunamycin], and (iii) acyclic polyketides [xanthocillin X dimethylether, (+)-trichostatin D, and (+)-actinopyrone A]. Features of the total syntheses are described. Original methodologies have been developed and applied to construct the inherent structures of the target molecules. Most syntheses cited herein are the first total syntheses, and the absolute structures of the target molecules have been determined. 相似文献