127793-68-4Relevant academic research and scientific papers
Synthesis of antineoplastic analogs of aplysiatoxin with various side chain structures
Shu, Yuki,Yanagita, Ryo C.,Tokuda, Harukuni,Suzuki, Nobutaka,Irie, Kazuhiro
, p. 281 - 303 (2013/08/23)
We have recently developed a simplified analog of aplysiatoxin with anti-proliferative activity (1). To investigate the structure-activity relationship of its side chain, an alternative synthetic route of 1 has been established. Via the key intermediate 6
Stereoselective synthesis and structural correction of the naturally occurring lactone stagonolide G
Angulo-Pachon, Cesar A.,Diaz-Oltra, Santiago,Murga, Juan,Carda, Miguel,Marco, J. Alberto
supporting information; experimental part, p. 5752 - 5755 (2011/03/19)
A convergent synthesis of the structure proposed for the naturally occurring lactone stagonolide G is described. All three stereocenters were created with the aid of asymmetric Brown allylations. The lactone ring was built by means of a ring-closing metat
Further improvement on sulfonamide-based ligand for catalytic asymmetric 2-haloallylation and allylation
Zhang, Zhiyu,Huang, Jian,Ma, Bin,Kishi, Yoshito
supporting information; experimental part, p. 3073 - 3076 (2009/05/11)
(Chemical Equation Presented) The sulfonamide-based ligand B was found to exhibit an outstanding crystallinity and perform well as a ligand for Cr-mediated catalytic asymmetric 2-haloallylation and allylation. The new ligand has an appealing advantage ove
Catalytic enantioselective allyl- and crotylboration of aldehydes using chiral diol·SnCl4 complexes. Optimization, substrate scope and mechanistic investigations
Rauniyar, Vivek,Zhai, Huimin,Hall, Dennis G.
supporting information; scheme or table, p. 8481 - 8490 (2009/02/02)
We report a novel class of C2-symmetric chiral diols derived from the hydrobenzoin skeleton. The combination of these diols with SnCl 4 under Yamamoto's concept of Lewis acid assisted Bronsted acidity (LBA catalysis) leads to high levels of asymmetric induction in the allylboration of aldehydes by commercially available allylboronic acid pinacol ester 1a. The corresponding homoallylic alcohol products of synthetically useful aliphatic aldehydes are obtained in excellent yields with up to 98:2 er. This combined acid manifold is also efficient in catalyzing the diastereo- and enantioselective crotylboration of aldehydes, thus providing the propionate units in >95:5 dr and up to 98:2 er. The X-ray crystal structure of the optimal diol·SnCl4 complex, Vivol (4m)·SnCl 4, unambiguously shows the Bronsted acidic character of this LBA catalyst and its highly dissymmetrical environment. Further controls have ruled out a possible boron transesterification mechanism with the chiral diol and point to LBA catalyst-derived activation of the pinacol allylic boronates 1. Due to slow dissociation of the diol·SnCl4 complex, a small excess of diol is required in order to suppress a competing racemic cycle catalyzed by free SnCl4.
Fully reagent-controlled asymmetric synthesis of (-)-Spongidepsin via the Zr-catalyzed asymmetric carboalumination of alkenes (ZACA reaction)
Zhu, Gangguo,Negishi, Ei-Ichi
, p. 2771 - 2774 (2008/02/07)
The ZACA reaction has been shown to proceed satisfactorily with internally OH-substituted 1-alkenes, provided that the OH group is unprotected and non-allylic. This reaction was used for reagent-controlled asymmetric construction of 3. Allylic alcohol was
Synthesis and assignment of the absolute configuration of the anti-Helicobacter pylori agents CJ-12,954 and CJ-13,014
Brimble, Margaret A.,Bryant, Christina J.
, p. 2858 - 2866 (2008/03/12)
The synthesis of the spiroacetal-containing anti-Helicobacter pylori agents (3S,2″S,5″S,7″S)-1a (ent-CJ-12,954) and (3S,2″S, 5″R,7″S)-2a (ent-CJ-13,014) has been carried out based on the convergent union of a 1: 1 mixture of heterocycle-activated spiroace
Synthesis of the spiroacetal-containing anti-Helicobacter pylori agents CJ-12,954 and CJ-13,014
Brimble, Margaret A.,Bryant, Christina J.
, p. 4506 - 4508 (2008/09/18)
The first synthesis of the spiroacetal-containing anti-Helicobacter pylori agents ent-CJ-12,954 and ent-CJ-13,014 is reported based on the union of a heterocycle-activated spiroacetal-containing sulfone fragment with a phthalide-containing aldehyde fragme
Fe/Cr- and Co/Cr-mediated catalytic asymmetric 2-haloallylations of aldehydes
Kurosu, Michio,Lin, Mei-Huey,Kishi, Yoshito
, p. 12248 - 12249 (2007/10/03)
The first example to couple aldehydes and 3-bromo-2-halopropenes in a catalytic asymmetric manner is reported. The coupling reaction is effected by the use of a chiral sulfonamide-Cr complex (prepared in situ from 1d, CrBr3, Fe(III) or from Co(II), Et3N, and Mn), TMSCl, and 2,6-lutidine. The method reported here is operationally simple and scalable, furnishing 3-halohomoallylic alcohols with a synthetically useful level of enantiomeric excess. Copyright
Diastereoselective synthesis of 2,5-disubstituted 3-hydroxypyrrolidine and 2,6-disubstituted 3-hydroxypiperidine derivatives by radical cyclisation; synthesis of (+)-bulgecinine and (-)-desoxoprosopinine
Yuasa, Yoko,Ando, Jun,Shibuya, Shiroshi
, p. 793 - 802 (2007/10/03)
Cyclisation of the O-stannyl ketyl, generated from the aldehyde 17 by reaction with tributyltin hydride in the presence of AIBN, gives the 5-benzyloxymethyl-7-hydroxypyrrolooxazolidin-2-ones as a diastereoisomeric mixture of 7α-ol 18 and 7β-ol 19 (2:1), with high diastereoselectivity with respect to the 5,7a positions. (+)-Bulgecinine 8 is enantioselectively synthesised by stereospecific reduction of the ketone 20, derived from compounds 18 and 19. In a similar way, cyclisation of compound 40 gives a 2:1 mixture of compounds 41 and 42. Conversion of compound 41 into (-)-desoxoprosopinine 9 is successfully achieved.
N,N'-Bis(2,2,2-trifluoroethyl)-N,N'-ethylenetartramide: An Improved Chiral Auxiliary for the Asymmetric Allylboration Reaction
Roush, William R.,Grover, Paul T.
, p. 3806 - 3813 (2007/10/02)
N,N'-Bis(2,2,2-trifluoroethyl)-N,N'-ethylenetartramide (8), synthesized by a simple four-step sequence from ethylenediamine and benzylidenetartaric acid, was designed in anticipation that the derived allylboronates 9-11 would display enhanced reactivity o
