- Highly Diastereoselective Cycloadditions via Chelation Control: Asymmetric Synthesis of β-Lactones
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Chelation controlled cycloadditions of trimethylsilylketene to chiral α- and β-benzyloxyaldehydes followed by desilylation provides a highly diastereoselective route to functionalized β-lactones.Several Lewis acids were examined and MgBr2*Et2O was found to give the highest diastereoselectivities and yields.
- Zemribo, Ronald,Romo, Daniel
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Read Online
- COMPOUNDS FOR USE IN THE TREATMENT OR PROPHYLAXIS OF PAIN, INFLAMMATION AND/OR AUTOIMMUNITY
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The present invention relates to a polymorphic form of (S,S)-2-N(3-O-(propan-2-ol)-1-propyl- 4-hydroxybenzene)-3-phenylpropylamide or synonymously named N-[2-(4-Hydroxy-phenyl)- -(2-hydroxy-propoxymethyl)-ethyl]-3-phenyl-propionamide and to the treatment
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Page/Page column 15
(2020/08/13)
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- 2 - (1 - hydroxyethyl), 2 - acetyl thiazole - 4 - carboxamides and application (by machine translation)
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The invention relates to a 2 - (1 - hydroxyethyl), 2 - acetyl thiazole - 4 - carboxamides and application. This kind of structure of the compound of the general formula (I). Wherein X is OH (BB series), =O (BA series); R2 Is C2 - C5 alkyl, subs
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Paragraph 0013; 0020; 0021
(2017/11/16)
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- Total synthesis and biological activity of dolastatin 16
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The total synthesis of dolastatin 16, a macrocyclic depsipeptide first isolated from the sea hare Dolabella auricularia as a potential antineoplastic metabolite by Pettit et al., was achieved in a convergent manner. Dolastatin 16 was reported by Tan to ex
- Casalme, Loida O.,Yamauchi, Arisa,Sato, Akinori,Petitbois, Julie G.,Nogata, Yasuyuki,Yoshimura, Erina,Okino, Tatsufumi,Umezawa, Taiki,Matsuda, Fuyuhiko
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supporting information
p. 1140 - 1150
(2017/02/10)
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- Acyclic 1,4-Stereocontrol via the Allylic Diazene Rearrangement: Development, Applications, and the Essential Role of Kinetic e Stereoselectivity in Tosylhydrazone Formation
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We report full details of a method for 1,3-reductive transposition of α-alkoxy-α,β-unsaturated hydrazones to provide E-alkenes with high 1,4-stereocontrol between the two respective allylic stereocenters. The process couples a chelation-controlled reduction of the hydrazone with an in situ allylic strain controlled retro-ene reaction of an allyl diazene, i.e., an allylic diazene rearrangement. Such stereotriads are frequently observed motifs in natural products. We observed a fortuitous kinetic preference for the E-hydrazone geometry during the hydrazonation reaction, as only the E-isomers could undergo chelation-controlled reduction.
- Shrestha, Maha L.,Qi, Wei,McIntosh, Matthias C.
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p. 8359 - 8370
(2017/08/23)
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- BENZAMIDE COMPOUNDS AS ROR GAMMA MODULATORS
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The present disclosure is directed to compounds of formula (I) and pharmaceutically acceptable salts thereof, wherein ring A, R1, R2, R3, R4, R5, n and p are as defined herein, which are active as modulators of retinoid-related orphan receptor gamma t (RORγt). These compounds prevent, inhibit, or suppress the action of RORγt and are therefore useful in the treatment of RORγt mediated diseases, disorders, syndromes or conditions such as, e.g., pain, inflammation, COPD, asthma, rheumatoid arthritis, colitis, multiple sclerosis, psoriasis, neurodegenerative diseases and cancer.
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Page/Page column 41
(2017/12/16)
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- Antineoplastic agents. 599. Total synthesis of dolastatin 16
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The first 23-step total synthesis of the cyclodepsipeptide dolastatin 16 (1) has been achieved. Synthesis of the dolaphenvaline and dolamethylleuine amino acid units using simplified methods improved the overall efficiency. The formation of the 25-membere
- Pettit, George R.,Smith, Thomas H.,Arce, Pablo M.,Flahive, Erik J.,Anderson, Collin R.,Chapuis, Jean-Charles,Xu, Jun-Ping,Groy, Thomas L.,Belcher, Paul E.,Macdonald, Christian B.
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p. 476 - 485
(2015/04/14)
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- Process for the Preparation of Triazole Antifungal Drug, Its Intermediates and Polymorphs Thereof
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A process for the preparation of 4-[4-[4-[4-[[(3R,5R)-5-(2,4-difluorophenyl)tetrahydro-5-(1H-1,2,4-triazol-1-ylmethyl)-3-furanyl]methoxy]phenyl]-1-piperazinyl]phenyl]-2-[(1S,2S)-1-ethyl-2-hydroxypropyl]-2,4-dihydro-3H-1,2,4-triazol-3-one compound of formula-1, its intermediates and polymorphs thereof. (I)
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- ISOLATED STEREOISOMERIC FORMS OF (S) 2-N (3-O-(PROPAN 2-OL) -1-PROPYL-4-HYDROXYBENZENE) -3-PHENYLPROPYLAMIDE
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The present invention relates to isolated stereoisomeric forms of the compound (S)2-N(3- 0-(propan 2-ol)-l-propyl-4-hydroxybenzene)-3-phenylpropylamide. Specifically, the present invention relates to the use of (S)2-N(3-0-((S)propan 2-ol)-l-propyl-4- hydr
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Page/Page column 15
(2013/06/27)
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- Total synthesis of incednam, the aglycon of incednine
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The first total synthesis of incednam (1), the aglycon of antibiotic incednine (2), is described. Incednine has been reported to exhibit significant inhibitory activity against the antiapoptotic oncoproteins Bcl-2 and Bcl-xL. The synthesis of 1 commenced
- Ohtani, Takashi,Tsukamoto, Shinya,Kanda, Hiroshi,Misawa, Kensuke,Urakawa, Yoshifumi,Fujimaki, Takahiro,Imoto, Masaya,Takahashi, Yoshikazu,Takahashi, Daisuke,Toshima, Kazunobu
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scheme or table
p. 5068 - 5071
(2010/12/25)
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- AGONISTS OF PEROXISOME PROLIFERATOR ACTIVATED RECEPTOR-α
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Disclosed are compounds of the formula: (I) And pharmaceutically acceptable salts thereof, wherein the variables are as defined herein, which are useful in activating PP ARa and in treating atherosclerosis hypercholesterolemia, primary hypercholesterolemi
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Page/Page column 97
(2010/08/05)
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- Chiral tetraphenylethenes as novel dopants for calamitic and discotic liquid crystals
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Three series of novel chiral tetraphenylethenes have been prepared: citronellyl-derived ethers 1a, b, lactate-derived ethers 2d, g, h, i and lactate-derived esters 3a-c, e-h. Helical twisting powers (HTPs) were determined for those derivatives of 1-3, whi
- Schreivogel, Alina,Dawin, Ute,Baro, Angelika,Giesselmannb, Frank,Laschat, Sabine
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experimental part
p. 484 - 494
(2010/04/05)
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- Synthesis and comparative antibacterial activity of verdamicin C2 and C2a. A new oxidation of primary allylic azides in dihydro[2H]pyrans
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(Chemical Equation Presented) A synthesis of verdamicin C2 and its congener C2a has been accomplished from sisomicin relying on a novel oxidative transformation of an allylic azide to the corresponding α,β- unsaturated aldehyde, and its stereocontrolled elaboration into the intended 5′ side chain of verdamicin C2 and C2a. In vitro antibacterial testing shows that both C6′ epimers in verdamicin C2 and C2a are equally active against a variety of bacterial strains. Oxidation of allylic primary azides, ethers, and esters of 2-substituted dihydro[2H]pyrans with SeO2 leads directly to the corresponding aldehydes.
- Hanessian, Stephen,Szychowski, Janek,Pablo Maianti
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supporting information; experimental part
p. 429 - 432
(2009/09/25)
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- Acyclic 1,4-stereocontrol via reductive 1,3-transpositions
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(Chemical Equation Presented) One-pot reduction/allylic diazene rearrangement of lactic acid- and mandelic acid-derived α,β- unsaturated tosyl hydrazones leads to 1,4-syn-or 1,4-anti-E-2-alkenyl arrays in high yield and diastereoselectivity. Either the syn or the anti diastereomer can be prepared by choosing the appropriate alkene stereoisomer of the hydrazone. The E-alkenes led to the 1,4-syn isomers, while the Z-alkenes led to the 1,4-anti isomers, both with ≥20:1 diastereoselectivity.
- Qi, Wei,McIntosh, Matthias C.
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p. 357 - 359
(2008/09/19)
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- Total synthesis of GEX1A
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(Chemical Equation Presented) An efficient and readily modifiable synthesis of GEX1A/herboxidiene/TAN-1609 (1) was developed. This modular synthesis featured a Suzuki coupling to install the conjugated diene and a Ru-catalyzed lactonization and Roush crotylation to construct the functionalized tetrahydropyran moiety. Myers' alkylation, cross-metathesis, and Keck crotylation were employed for assembly of the biologically essential side-chain domain.
- Murray, Timothy J.,Forsyth, Craig J.
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supporting information; experimental part
p. 3429 - 3431
(2009/05/11)
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- A unified synthetic approach to polyketides having both skeletal and stereochemical diversity
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An efficient systematic approach to the diversity-oriented synthesis of polyketides has been developed to provide both skeletal and stereochemical diversity. Each synthetic intermediate is also a desired polyketide fragment and no protecting group manipul
- Shang, Shiying,Iwadare, Hayato,Macks, Daniel E.,Ambrosini, Lisa M.,Tan, Derek S.
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p. 1895 - 1898
(2008/02/12)
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- Prototype of a photoswitchable foldamer
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(Figure Presented) Know where to fold 'em: A foldamer exhibiting a light-induced helix-coil transition (see scheme) can be constructed by introducing a photochromic azobenzene moiety (red) into the center of an amphiphilic phenylene ethynylene backbone (blue). This system gives insight into folding and unfolding mechanisms and promises applications in photoresponsive (bio)materials and "smart" delivery devices based on photoresponsive dynamic receptors.
- Khan, Anzar,Kaiser, Christian,Hecht, Stefan
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p. 1878 - 1881
(2007/10/03)
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- Glycosidation via conjugate addition of anomeric alkoxides to nitroalkenes and nitrosoalkenes
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The conjugate addition reactions of protected pyranose alkoxides to both nitroalkenes and nitrosoalkenes, as a route to 2-nitroalkyl, 2-oximinoalkyl and 2-oxoalkyl glycosides, are described.
- Trewartha, Gary,Burrows, Jeremy N.,Barrett, Anthony G. M.
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p. 3553 - 3556
(2007/10/03)
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- Stereoselective synthesis of functionalised triol units by SnCl4 promoted allylation of α-benzyloxyaldehydes: Crucial role of the stoichiometry of the Lewis acid
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Enantiomerically pure syn-anti and syn-syn configured triol units are efficiently synthesized by the SnCl4 mediated allylation of chiral α-benzyloxyaldehydes with the uniquely functionalised allylstannane 9. Remarkably, the stereochemistry of t
- Dubost, Christophe,Leroy, Bernard,Markó, Istvan E.,Tinant, Bernard,Declercq, Jean-Paul,Bryans, Justin
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p. 7693 - 7704
(2007/10/03)
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- The use of nonactivated iminodienophiles in the stereoselective aza-Diels-Alder reaction
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This paper describes the preparation of nitrogen-containing bicycles by the aza-Diels-Alder reaction of nonactivated iminodienophiles and cyclopentadiene. Readily available starting materials such as (S)-(-)-lactate and L-amino acids were used for the pre
- Trifonova, Anna,Andersson, Pher G.
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p. 445 - 452
(2007/10/03)
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- The "Aqueous" Prins Reaction
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(Equation presented) In this communication we demonstrate that Prins cyclization reactions occur under very mild conditions when cyclic α,β-unsaturated acetals are employed as oxocarbenium ion progenitors and allylsilanes are used as nucleophiles. Cycliza
- Aubele, Danielle L.,Lee, Christopher A.,Floreancig, Paul E.
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p. 4521 - 4523
(2007/10/03)
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- Enantiomerically-enhanced nutritional energy substrates
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Synthetic enantiomeric esters are employed as energy substrates for parenteral or enteral nutritional formulations. The substrates are provided in substantially monoisomeric or anomeric forms readily utilized in patient metabolism.
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- Stereoselective total synthesis of zaragozic acid A based on an acetal [1,2] Wittig rearrangement
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A simultaneous creation of the C4 and C5 quaternary carbon centers by an acetal [1,2] Wittig rearrangement of O-glycoside 1 derived from L-arabino-γ-lactone is the key feature in the construction of the 2,8-dioxabicyclo[3.2.1]octane core structure of zara
- Tomooka, Katsuhiko,Kikuchi, Makoto,Igawa, Kazunobu,Suzuki, Masaki,Keong, Ping-Huai,Nakai, Takeshi
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p. 4502 - 4505
(2007/10/03)
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- Activation of the reverse-cope elimination by allylic oxygen functions: Syntheses of (-)-hygroline and (+)-pseudohygroline
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Reverse-Cope cyclisations of N-(4-alkenyl)hydroxylamines 8 are accelerated by the presence of the allylic oxygen function; this has been applied to a brief synthesis of the alkaloids (-)-hygroline 6 and (+)- pseudohygroline 7.
- Knight, David W.,Salter, Rhys
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p. 5915 - 5918
(2007/10/03)
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- Stereoselective Bromination of Dehydroamino Acids with Controllable Retention or Inversion of Olefin Configuration
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Dehydroamino acids react with brominating reagents to produce syn-α-bromo imines as the major products, which undergo tautomerization to mixtures of the diastereomeric (E)- and (Z)-β-bromo-α,β-dehydroamino acids upon treatment with base.Herein, we examine
- Coleman, Robert S.
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p. 4452 - 4461
(2007/10/02)
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- Diastereoselectivity of the thio-Claisen rearrangement of acyclic precursors bearing a chiral centre adjacent to carbon 6
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A number of chiral allylic alcohols have been prepared and submitted to a Mitsunobu reaction with dithioacetic acid. Allyl dithioesters were deprotonated by LDA at -30°C and resulting enethiolates were quenched with iodomethane to afford quantitatively S-
- Desert, Stephane,Metzner, Patrick
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p. 10327 - 10338
(2007/10/02)
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