- Studies toward the Total Syntheses of Calyciphylline D-Type Daphniphyllum Alkaloids
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An efficient construction of an aza-[5.7.6.5] tetracyclic core structure of calyciphylline D-type Daphniphyllum alkaloids has been achieved. The synthetic route features a diastereoselective cyclopropanation, efficient construction of the core bridged 8-aza-[3.2.1]octane skeleton through a [3 + 2] IMCC strategy, oxidative dearomatization of phenol, and gram-scale preparation in each step.
- Cui, Yi,Ren, Jun,Lv, Jiayuan,Wang, Zhongwen
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supporting information
p. 9189 - 9193
(2021/11/30)
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- ACYLAMINO BRIDGED HETEROCYCLIC COMPOUND, AND COMPOSITION AND APPLICATION THEREOF
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Provided are an acylamino bridged heterocyclic compound of formula (I) or a pharmaceutically acceptable salt, an isomer, a solvate, a crystal, or a prodrug thereof, and a pharmaceutical composition comprising the compound, and an application of the compou
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Paragraph 0174
(2021/11/04)
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- ANTAGONISTS OF HUMAN INTEGRIN (ALPHA4)(BETA7)
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Disclosed are small molecule antagonists of α4β7 integrin, and methods of using them to treat a number of specific diseases or conditions.
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Paragraph 0228; 0775; 0776
(2019/10/29)
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- 1,2-asymmetric induction in diastereoselective zwitterionic aza-Claisen rearrangements: Key steps in optically active alkaloid synthesis
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The zwitterionic aza-Claisen rearrangement of optically active N-allylpyrrolidines and α-phenoxyacetyl fluorides proceeds with complete simple diastereoselectivity (internal asymmetric induction) and complete 1,2-asymmetric induction to generate a new C-C bond adjacent to a chiral C-N-Boc functionality. The resulting γ,δ-unsaturated amides were cyclised to give the corresponding pyrrolizidinones, which enabled the determination of the relative configuration of the stereotriads. Vinyl group degradation and a final lactam reduction gave an optically active analogue of (+)-petasinine (a pyrrolizidine alkaloid). Furthermore, the stereotriad-containing amides should be useful key intermediates for the total synthesis of optically active elaeocarpin (an indolizidine alkaloid). Copyright
- Heescher, Carolin,Schollmeyer, Dieter,Nubbemeyer, Udo
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supporting information
p. 4399 - 4404
(2013/07/26)
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- INHIBITORS OF THE RENAL OUTER MEDULLARY POTASSIUM CHANNEL
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The present invention provides compounds of Formula (I) and the pharmaceutically acceptable salts thereof, which are inhibitors of the ROMK (Kir1.1) channel. The compounds act as diuretics and natriuretics and are valuable pharmaceutically active compounds for the therapy and prophylaxis of medical conditions including cardiovascular diseases such as hypertension and conditions resulting from excessive salt and water retention.
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Page/Page column 70
(2013/07/05)
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- Design of living ring-opening alkyne metathesis
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It's alive: A ring-strained alkyne based on dibenzo[a,e][8]annulene undergoes ringopening metathesis polymerization (ROMP) to give a high-molecular-weight poly(ortho-phenylene) featuring alternating ethyl and ethynyl linkers along the polymer backbone. The molybdenumalkylidyne- based catalyst system discriminates between strained and unstrained alkynes to yield a living polymer with an unparalleled low polydispersity.
- Fischer, Felix R.,Nuckolls, Colin
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supporting information; experimental part
p. 7257 - 7260
(2010/11/05)
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- Reaction of methyl 4,5-epoxy-(2E)-pentenoate with arylcopper reagents
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The reaction of methyl 4,5-epoxy-(2E)-pentenoate (1) with various arylcopper reagents was studied. Basically, all arylcopper reagents react with 1 in SN2 fashion. However, addition of BF3 causes reversal of the regioselectivity, which can be ra
- Nagumo,Irie,Akita
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p. 675 - 680
(2007/10/03)
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- Collisionally induced dissociation in the study of A-ring hydroxylated vitamin D type compounds
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Colllslonally Induced dissociation (CID) is often used to determine the structure of ions based on comparison with the CID spectra of known ions. The latter are generated from Judiciously selected compounds taking into account basic principles of Ion chemistry. We report here on the use of this approach toward determination of the site of A-ring hydroxylation of vitamin D. Although not Intrinsically an aromatic compound, vitamin D gives rise in its mass spectrum to an aromatic methytstyryl cation at mlz 118. A-ring hydroxylated metabolites of vitamin D would thus Incorporate the extra OH group on the ion at mlz 118, shifting it to mlz 134. The position of substitution of the extra OH group on a metabolite could then be ascertained by comparing the CID spectrum of its mlz 134 fragment to those of the four possible (hydroxymethyl)styryl cations generated from synthesized authentic compounds. Because of their propensity to polymerize, these cations were generated in situ via the McLafferty rearrangement of the corresponding (hydroxyphenyl)ethanols. For optimum differentiation of Isomeric Ions, preparation of permethylated derivatives of vitamin D was necessary. The validity of the hypothesis was verified using 1,25-dihydroxy-vitamin D3 as a test compound. This method provides a viable approach for the characterization of A-ring hydroxylated metabolites of vitamin D as well as for related aromatic compounds.
- Young, David C.,Vouros, Paul,Holick, Michael F.,Higuchi, Tetsuo
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p. 837 - 842
(2007/10/02)
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