37031-29-1Relevant articles and documents
Synthesis of (+)-goniopypyrone and (+)-goniotriol using Pd-catalyzed carbonylation
Miyazawa, Yuki,Sugimoto, Makoto,Tanaka-Oda, Ayumi,Makabe, Hidefumi
, (2019/08/16)
Syntheses of (+)-goniopypyrone and (+)-goniotriol isolated from Goniothalamus giganteus were achieved. The key steps involve Pd-catalyzed carbonylation for lactone ring formation and diastereoselective reduction of ynone using the (R)-CBS catalyst and borane dimethyl sulfide complex.
Chiroptical properties of 2,2’-bioxirane
Daugey,De Rycke,Brotin,Buffeteau
supporting information, p. 342 - 350 (2018/01/15)
The two enantiomers of 2,2′-bioxirane were synthesized, and their chiroptical properties were thoroughly investigated in various solvents by polarimetry, vibrational circular dichroism (VCD), and Raman optical activity (ROA). Density functional theory (DFT) calculations at the B3LYP/aug-cc-pVTZ level revealed the presence of three conformers (G+, G?, and cis) with Gibbs populations of 51, 44, and 5% for the isolated molecule, respectively. The population ratios of the two main conformers were modified for solvents exhibiting higher dielectric constants (G? form decreases whereas G+ form increases). The behavior of the specific optical rotation values with the different solvents was correctly reproduced by time-dependent DFT calculations using the polarizable continuum model (PCM), except for the benzene for which explicit solvent model should be necessary. Finally, VCD and ROA spectra were perfectly reproduced by the DFT/PCM calculations for the Boltzmann-averaged G+ and G? conformers.
Stereocontrolled synthesis of four isomeric linoleate triols of relevance to skin barrier formation and function
Davis, Robert W.,Allweil, Alexander,Tian, Jianhua,Brash, Alan R.,Sulikowski, Gary A.
supporting information, p. 4571 - 4573 (2018/11/23)
Linoleate triol esters are intermediates along the pathway of formation of the mammalian skin permeability barrier. In connection with the study of their involvement in barrier formation we required access to isomerically pure and defined samples of four linoleate triol esters. A common synthetic strategy was developed starting from isomeric alkynols derived from D-tartaric acid and 2-deoxy-D-ribose.
Convergent Synthesis of the Dihydropyran Core Containing the C1-C15 Subunit of Sorangicin A Employing Gold(I)-Catalyzed Cyclization of an Allenic Alcohol
Raghavan, Sadagopan,Nyalata, Satyanarayana
supporting information, p. 10698 - 10706 (2016/11/29)
A convergent route to the C1-C15 subunit of sorangicin A is disclosed. The key steps include carbon-carbon bond formation using an α-chloro sulfide, regioselective hydrozirconation of an internal alkyne for the preparation of a trisubstituted iodoalkene, allene formation using the Myers-Movassaghi protocol, stereoselective reduction of allylic and propargylic ketones using Noyori's catalyst, and gold(I)-catalyzed cyclization of a β-hydroxy allene to construct the dihydropyran ring.
Design of Highly Stable Iminophosphoranes as Recyclable Organocatalysts: Application to Asymmetric Chlorinations of Oxindoles
Gao, Xing,Han, Jianwei,Wang, Limin
supporting information, p. 4596 - 4599 (2015/09/28)
A new family of tartaric acid derived chiral iminophosphoranes has been developed as highly effective organocatalysts in the asymmetric chlorinations of 3-substituted oxindoles with a high level of enantioselectivity. Importantly, these catalysts are air- and moisture-stable. Recovery of the catalyst after simple chromatographic separation for reuse in the model reaction was achieved; the catalyst can be recycled six times without loss of any enantioselectivity. Several advantages of this catalytic process are high conversion after a very short reaction time at ambient temperature, low catalytic loading, and scale-up to multigram quantities with an excellent enantiomeric excess value of >99%, which meets the enantiomeric purity required for pharmaceutical purposes.
Versicolactones A and B: Total synthesis and structure revision
Wang, Liping,Zhu, Weiming
supporting information, p. 6729 - 6731 (2013/11/19)
To further determine absolute configurations of versicolactones A and B, total synthesis of versicolactones A and B and their six stereoisomers were reported in this Letter. The 1H and 13C NMR spectra of the synthetic erythro-stereoisomers matched perfectly with those of the natural products. Combined with the comparison of the specific rotations, the absolute configuration of versicolactones A and B were revised as (4Z,6R,7S)- and (4E,6R,7S)- from the corresponding (4Z,6R,7R)- and (4E,6R,7R)-6,7-dihydroxyocta- 2,4-dien-4-lactone, respectively.
A Total synthesis of aliskiren starting from D-Tartrate diester
Kim, Ji Hei,Ko, Soo Y.
, p. 3777 - 3781 (2014/01/17)
A formal total synthesis of aliskiren was accomplished. A key in our synthesis was to use the symmetric ciscisoid-Cis-Bis-Lactone 3' as a precursor, which was prepared from D-tartrate diester. Appending the end groups and functional group transformations completed the synthesis.
A C2-symmetric pool based flexible strategy: An enantioconvergent synthesis of (+)-valiolamine and (+)-valienamine
Lo, Hong-Jay,Chen, Cheng-Yih,Zheng, Wei-Lin,Yeh, Shang-Ming,Yan, Tu-Hsin
experimental part, p. 2780 - 2785 (2012/07/14)
A new enantioconvergent strategy directed toward the synthesis of glucosidase inhibitors was developed by using a C2-symmetric element within the chiral pool and by applying an iodine-promoted cyclization of an unsaturated carbonimidothioate for the regio- and diastereocontrolled installation of amino and hydroxy units. Not only does this simple flexible strategy provide a convergent concise approach to (+)-valiolamine (1), but it can also be readily adopted for the synthesis of (+)-valienamine (2). Commercially available and cheap C2-symmetric D-tartaric acid served as the chiral building block. Copyright
Chiral pool based efficient synthesis of the aminocyclitol core and furanoside of (-)- hygromycin A: Formal total synthesis of (-)-hygromycin A
Lo, Hong-Jay,Chang, Yuan-Kang,Yan, Tu-Hsin
supporting information, p. 5896 - 5899 (2013/02/23)
A chiral pool based synthetic strategy that leads from the readily available and inexpensive C2-symmetric tartaric acids to the chiral O-isopropylidenebenzooxazolei- a convenient precursor to the aminocyclitol core of hygromycin A as well as the chiral γ-disilyloxybutyrolactone-a pivotal intermediate to approach to the furanoside of hygromycin A.
A C2-symmetric pool based synthesis of the furanoside of hygromycin A
Lo, Hong-Jay,Chang, Yuan-Kang,Lin, Feng-Yi,Yan, Tu-Hsin
, p. 687 - 695 (2013/08/15)
The readily available and inexpensive D-tartaric acid serves as the chiral building block for synthesis of the furanoside of hygromycin A. Key to our successes in the asymmetric synthesis of the furanose segment was the melding of several key reactions, such as the successful application of the monosilylation of C2-symmetric diol, diastereocontrolled di(2-propenyl)zinc addition to the aldehyde, and TMSCl-MeOH promoted desilylation, acetal-cleavage, and intramolecular esterification in one-step.