94594-90-8Relevant academic research and scientific papers
Palladium-Catalyzed Stereoselective Cyclization of in Situ Formed Allenyl Hemiacetals: Synthesis of Rosuvastatin and Pitavastatin
Spreider, Pierre A.,Breit, Bernhard
supporting information, p. 3286 - 3290 (2018/06/11)
A diastereoselective palladium-catalyzed cyclization of allenyl hemiacetals is described. It permits the selective synthesis of 1,3-dioxane derivatives, precursors for syn-configured 1,3-diols which make an appearance in all of the statin representatives. The reaction allows the total synthesis of Rosuvastatin and Pitavastatin in a straightforward fashion.
Stereoselective α-Hydroxylation of Amides Using Oppolzer's Sultam as Chiral Auxiliary
Zhang, Lumin,Zhu, Lili,Yang, Jun,Luo, Jisheng,Hong, Ran
, p. 3890 - 3900 (2016/05/24)
An Oppolzer's sultam-based highly stereoselective α-hydroxylation of amides was developed to deliver the desired products in good yield and excellent diastereoselectivity (>20/1). The generally crystalline products and the recyclability of the chiral auxiliary illustrate the practicability and scalability of the current approach.
Tosvinyl and besvinyl as protecting groups of imides, azinones, nucleosides, sultams, and lactams. Catalytic conjugate additions to tosylacetylene
Petit, Elena,Bosch, Llus,Font, Joan,Mola, Laura,Costa, Anna M.,Vilarrasa, Jaume
, p. 8826 - 8834 (2015/01/08)
The use of the 2-(4-methylphenylsulfonyl)-ethenyl (tosvinyl, Tsv) group for the protection of the NH group of a series of imides, azinones (including AZT), inosines, and cyclic sulfonamides has been examined. The Tsvprotected derivatives are obtained in excellent yields by conjugate addition to tosylacetylene (ethynyl p-tolyl sulfone). The stereochemistry of the double bond can be controlled at will: with only 1 mol % of Et3N or with catalytic amounts of NaH, the Z stereoisomers are generated almost exclusively, while the E isomers are obtained using a stoichiometric amount of DMAP. Analogous phenylsulfonylvinyl-protected groups (with the besvinyl or Bsv group instead of Tsv) are obtained stereospecifically by reaction with (Z)- or (E)-bis(phenylsulfonyl)ethene. For lactams and oxazolidinones, this last method is much better. The Tsv and Bsv groups are stable in the presence of non-nucleophilic bases and to acids. They can be removed highly effectively via a conjugate addition-elimination mechanism using pyrrolidine or sodium dodecanethiolate as nucleophiles.
Amphidinolide B: Total synthesis, structural investigation, and biological evaluation
Lu, Liang,Zhang, Wei,Nam, Sangkil,Horne, David A.,Jove, Richard,Carter, Rich G.
, p. 2213 - 2247 (2013/05/09)
The total syntheses of amphidinolide B1 and the proposed structure of amphidinolide B2 have been accomplished. Key aspects of this work include the development of a practical, non-transition-metal-mediated method for the construction of the C13-C15 diene, the identification of α-chelation and dipole minimization models for diastereoselective methyl ketone aldol reactions, the discovery of a spontaneous Horner-Wadsworth-Emmons macrocyclization strategy, and the development of a novel late stage method for construction of an allylic epoxide moiety. The originally proposed structure for amphidinolide B2 and diastereomers thereof display potent antitumor activities with IC50 values ranging from 3.3 to 94.5 nM against human solid and blood tumor cells. Of the different stereoisomers, the proposed structure of amphidinolide B2 is over 12-fold more potent than the C8,9-epimer and C18-epimer in human DU145 prostate cancer cells. These data suggest that the epoxide stereochemistry is a significant factor for anticancer activity.
A facile, inexpensive and scalable route to thiol-protected α-methyl cysteine
Johnston, Heather J.,Hulme, Alison N.
supporting information, p. 591 - 594 (2013/04/10)
A facile, scalable synthesis of α-methyl cysteine with three alternate thiol protecting groups (trityl, allyl and tert-butyl) is described. The thiol-protected amino acids are obtained in six steps from l-cysteine ethyl ester and are ideally suited for a range of natural product and solid-phase peptide synthesis applications. Georg Thieme Verlag Stuttgart - New York.
Stereoselective synthesis of (3S,5S,6S)-tetrahydro-6-isopropyl-3,5- dimethylpyran-2-one; A C5-epimer of a component of a natural sex pheromone of the wasp Macrocentrus grandii, the larval parasitoid of the European corn borer Ostrinia nubilalis
Shklyaruck, Denis,Matiushenkov, Evgenii
experimental part, p. 1448 - 1454 (2011/11/12)
(3S,5S,6S)-Tetrahydro-6-isopropyl-3,5-dimethylpyran-2-one, a C5-epimer of a component of the natural sex pheromone of the wasp Macrocentrus grandii, the larval parasitoid of the European corn borer Ostrinia nubilalis, was synthesized starting from methyl l-valinate. The transformation includes a Kulinkovich cyclopropanation reaction, a cationic cyclopropyl-allyl rearrangement of cyclopropyl methanesulfonate, a diastereoselective alkylation of Oppolzer's (N-propionyl)-(2R)-bornane-10,2-sultam and a diastereoselective hydrogenation using Wilkinson's catalyst as the key steps.
Efficacious preparation of Oppolzer's glycylsultam via the Delepine reaction
Isleyen, Alper,Gonsky, Carolyn,Ronald, Robert C.,Garner, Philip
experimental part, p. 1261 - 1264 (2009/12/07)
A new preparative route to Oppolzer's glycylsultam, the 'NC' component in the asymmetric [C+NC+CC] coupling reaction leading to functionalized pyrrolidines, is described. The synthesis features a novel application of the Delepine reaction, providing a saf
Process for Production of Optically Active Carboxlic Acid Compound
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Page/Page column 6, (2009/05/28)
An optically active acylated camphorsultam can be hydrolyzed with an aqueous solution of an alkaline earth metal hydroxide in the presence of a branched alkanol, to give a corresponding optically active carboxylic acid compound in safely and inexpensively
Diastereoselective allylation of N-glyoxyloyl-(2R)-bornane-10,2-sultam and (1R)-8-phenylmenthyl glyoxylate: Synthesis of (2S,4S)-2-hydroxy-4-hydroxymethyl- 4-butanolide
Kiegiel, Katarzyna,Balakier, Tomasz,Kwiatkowski, Piotr,Jurczak, Janusz
, p. 3869 - 3878 (2007/10/03)
The diastereoselective addition of allylsilanes and allylstannanes to N-glyoxyloyl-(2R)-bornane-10,2-sultam 1 and (1R)-8-phenylmenthyl glyoxylate 7 in the presence of Lewis acids has been studied. We obtained diastereoselectivities up to 84% and 94% for the allylation of 2 and 7, respectively. The application of the allylation products of 1 or 2 in the synthesis of 4-butanolides, for example (2S,4S)-2-hydroxy-4-hydroxymethyl-4- butanolide 13 is presented.
