- Discriminating non-ylidic carbon-sulfur bond cleavages of sulfonium ylides for alkylation and arylation reactions
-
A sulfonium ylide participated alkylation and arylation under transition-metal free conditions is described. The disparate reaction pattern allowed the separate activation of non-ylidic S-alkyl and S-aryl bond. Under acidic conditions, sulfonium ylides serve as alkyl cation precursors which facilitate the alkylations. While under alkaline conditions, cleavage of non-ylidic S-aryl bond produces O-arylated compounds efficiently. The robustness of the protocols were established by the excellent compatibility of wide variety of substrates including carbohydrates.
- Fang, Jing,Li, Ting,Ma, Xiang,Sun, Jiuchang,Cai, Lei,Chen, Qi,Liao, Zhiwen,Meng, Lingkui,Zeng, Jing,Wan, Qian
-
supporting information
p. 288 - 292
(2021/07/25)
-
- Ring-closing metathesis approaches towards the total synthesis of rhizoxins
-
Efforts are described towards the total synthesis of the bacterial macrolide rhizoxin F, which is a potent tubulin assembly and cancer cell growth inhibitor. A significant amount of work was expanded on the construction of the rhizoxin core macrocycle by ring-closing olefin metathesis (RCM) between C(9) and C(10), either directly or by using relay substrates, but in no case was ringclosure achieved. Macrocycle formation was possible by ring-closing alkyne metathesis (RCAM) at the C(9)/C(10) site. The requisite diyne was obtained from advanced intermediates that had been prepared as part of the synthesis of the RCM substrates. While the direct conversion of the triple bond formed in the ring-closing step into the C(9)-C(10) E double bond of the rhizoxin macrocycle proved to be elusive, the corresponding Z isomer was accessible with high selectivity by reductive decomplexation of the biscobalt hexacarbonyl complex of the triple bond with ethylpiperidinium hypophosphite. Radical-induced double bond isomerization, full elaboration of the C(15) side chain, and directed epoxidation of the C(11)-C(12) double bond completed the total synthesis of rhizoxin F.
- Altmann, Karl-Heinz,Liniger, Marc,Neuhaus, Christian M.
-
supporting information
(2020/10/18)
-
- Bombyx uterol ester (((R)-(-)-3-2- R) and its derivatives) and synthetic method thereof (by machine translation)
-
The invention discloses a synthetic method of ((R)- (-) - 3 - rhodanshi ester (R)-2-methyl) propionate (methyl propionate) and a derivative thereof. To the synthetic method disclosed by the (S)- 4 - invention, as a raw material, a series of reactions such as acylation, substitution, hydrolysis, esterification, hydrogenation and ((R)- (-) - 3 - the like are synthesized to synthesize the Rogoligoligoligoligosl)-methyl propionate and derivatives thereof. The synthesis method is equally applicable to the synthesis of its enantiomers and derivatives thereof. The method has the advantages of short reaction time, high yield, good chiral selectivity, suitability for industrial production and the like. The invention relates to a roshi ester and a derivative structure thereof. . (by machine translation)
- -
-
Paragraph 0086-0089
(2019/11/29)
-
- Preparation of Alkyl Ethers with Diallyltriazinedione-Type Alkylating Agents (ATTACKs-R) Under Acid Catalysis
-
Diallyltriazinedione-type acid-catalyzed alkylating agents (ATTACKs-R) with 10 different alkyl groups (R), including benzyl, substituted benzyl, allyl, and methyl groups were synthesized. The palladium-catalyzed intramolecular O-to-N allylic rearrangement of 2,4-bis(allyloxy)-6-chloro-1,3,5-triazine was developed to introduce various alkoxy groups into the N,N′-dialkylated triazinedione skeleton. O-Alkylation of alcohols with ATTACKs-R was carried out in 1,4-dioxane in the presence of 2,6-di-tert-butylpyridinium trifluoromethanesulfonate or trifluoromethanesulfonic acid as a catalyst. Six selected ATTACKs-R bearing benzylic R groups were employed to prepare alkyl ethers from primary, secondary, and tertiary alcohols. The reactions of ATTACKs-R bearing an o-nitro-substituted benzyl group tended to afford low yields. Comparison of four different triazinedione-based benzylating reagents suggested that the N,N′-substituents affected the reactivity.
- Fujita, Hikaru,Yamashita, Rina,Fujii, Takanori,Yamada, Kohei,Kitamura, Masanori,Kunishima, Munetaka
-
p. 4436 - 4446
(2019/07/03)
-
- Progress toward the total synthesis of mirabalin isomers
-
Key fragments of the cytotoxic marine macrolide mirabalin have been synthesized, by using a flexible strategy based on asymmetric reductions to control the hydroxy- and carbamate-bearing stereocenters. In particular, ruthenium or rhodium-mediated asymmetric hydrogenation and transfer hydrogenation were used in combination with a dynamic kinetic resolution to control two contiguous stereocenters in a single step.
- Echeverria, Pierre-Georges,Pons, Amandine,Prévost, Sébastien,Férard, Charlène,Cornil, Johan,Guérinot, Amandine,Cossy, Janine,Phansavath, Phannarath,Ratovelomanana-Vidal, Virginie
-
-
- Development of triazine-based benzylating reagents possessing T-butyl group on the triazine core: Thermally controllable reagents for the initiation of reaction
-
Benzylating reagents, 4-(4,6-di-t-butyl-1,3,5-triazin-2-yl)-4-benzylmorpholinium triflate, and related derivatives have been developed. The reagents release benzyl triflate as a benzyl cation equivalent upon heating the solution to 40°C under neutral conditions. The O-benzylation of alcohols using a stoichiometric amount of these reagents afforded corresponding benzyl ethers in good to high yields. This was due to the presence of a bulky t-butyl group on the triazine ring of these reagents that prevents the consumption of benzyl triflate via a side reaction with a morpholinotriazine derivative.
- Karuo, Yukiko,Yamada, Kohei,Kunishima, Munetaka
-
p. 303 - 308
(2018/03/09)
-
- N,N′-Dimethylated Benzyloxytriazinedione: A Stable Solid Reagent for Acid-Catalyzed O-Benzylation
-
N,N′-Dimethylated 6-(benzyloxy)-1,3,5-triazine-2,4(1H,3H)-dione (DMBOT) has been developed as a triazinedione-based, stable solid reagent for acid-catalyzed O-benzylation. The conceptual basis of the design was to fix the core triazinedione skeleton, and
- Fujita, Hikaru,Kakuyama, Satoshi,Kunishima, Munetaka
-
supporting information
p. 833 - 839
(2017/02/15)
-
- TRIAZINE DIONE COMPOUND
-
PROBLEM TO BE SOLVED: To provide a novel triazine dione compound useful as an alkylating agent for a nucleophilic compound. SOLUTION: This invention relates to a compound represented by formula (I) [where each symbol is as defined in the specification] and an alkylating agent comprising the compound, and a method for alkylating a nucleophilic compound using the alkylating agent. SELECTED DRAWING: None COPYRIGHT: (C)2017,JPOandINPIT
- -
-
Paragraph 0127; 0129-0131
(2017/07/11)
-
- Total synthesis of odoamide, a novel cyclic depsipeptide, from an Okinawan marine cyanobacterium
-
Odoamide is a novel cyclic depsipeptide with highly potent cytotoxic activity isolated from the Okinawan marine cyanobacterium Okeania sp. It contains a 26-membered macrocycle composed of a fatty acid moiety, a peptide segment and isoleucic acid. Four pos
- Kaneda, Masato,Sueyoshi, Kosuke,Teruya, Toshiaki,Ohno, Hiroaki,Fujii, Nobutaka,Oishi, Shinya
-
p. 9093 - 9104
(2016/10/07)
-
- Callipeltosides A, B and C: Total Syntheses and Structural Confirmation
-
Since their isolation almost 20 years ago, the callipeltosides have been of long standing interest to the synthetic community owing to their unique structural features and inherent biological activity. Herein we present our full research effort that has led to the synthesis of these molecules. Key aspects of our final strategy include 1) synthesis of the C1-C9 pyran core (5) using an AuCl3-catalysed cyclisation; 2) formation of C10-C22 vinyl iodide (55) by sequential bidirectional Stille reactions and 3) diastereoselective union of these advanced fragments by means of an alkenylzinc addition (d.r.=91:9 at C9). The common callipeltoside aglycon (4) was completed in a further five steps. Following this, all three sugar fragments were appended to provide the entire callipeltoside family. In addition to this, D-configured callipeltose B was synthesised and appended to the callipeltoside aglycon. The 1H NMR spectrum of this molecule was found to be significantly different to the natural isolate, further supporting our assignment of callipeltoside B (2). Easy as A, B, C: The entire callipeltoside family of natural products have been synthesised in a highly convergent manner. This account details our full research effort and presents further evidence to aid in the stereochemical assignment of the glycosidic linkages present in callipeltosides B and C (see scheme).
- Frost, James R.,Pearson, Colin M.,Snaddon, Thomas N.,Booth, Richard A.,Turner, Richard M.,Gold, Johan,Shaw, David M.,Gaunt, Matthew J.,Ley, Steven V.
-
p. 13261 - 13277
(2015/09/15)
-
- Finding the Selectivity Switch - A Rational Approach towards Stereocomplementary Variants of the Ene Reductase YqjM
-
Ene reductases from the Old Yellow Enzyme family are versatile biocatalysts useful for the synthesis of optically active compounds. One disadvantage of biocatalysts when compared to competing catalysts in chemical syntheses is that often only one stereoisomer of the product is available. Another drawback can be the lack of activity in certain enzyme-substrate combinations. We were able to approach both of these challenges rationally in the case of the enzymatic synthesis of methyl 3-hydroxy-2-methylpropanoate (commonly denoted as the Roche ester) and derivatives thereof using the ene reductase YqjM. By a highly efficient, concept-based approach of designing mutant variants of YqjM and engineering substrates we could alter both the rate constant and the enantioselectivity of the reaction. Preparative scale reactions have been performed with successful mutants. In addition, the iterative modification of the substrate gave experiment-based insights into the binding mode of the Roche ester precursor and its derivatives.
- Rüthlein, Elisabeth,Classen, Thomas,Dobnikar, Lina,Sch?lzel, Melanie,Pietruszka, J?rg
-
supporting information
p. 1775 - 1786
(2015/06/02)
-
- Development of a new benzylating reagent spontaneously releasing benzyl cation equivalents at room temperature
-
A new O-benzylating reagent, that is, 4-(4,6-diphenoxy-1,3,5-triazin-2-yl)-4-benzylmorpholinium trifluoromethanesulfonate (DPT-BM), has been developed. Benzyl cation equivalents are generated from DPT-BM by dissolving the compound in a solvent at room tem
- Yamada, Kohei,Tsukada, Yuichi,Karuo, Yukiko,Kitamura, Masanori,Kunishima, Munetaka
-
supporting information
p. 12274 - 12278
(2015/03/31)
-
- Synthesis of a C1-C11 fragment of Zincophorin using planar chiral, neutral π-allyl iron complexes
-
A key step in the synthesis of a C1-C11 fragment of the ionophore antibiotic Zincophorin involves the addition of an α-alkoxyalkylcopper(i) reagent to a planar chiral, neutral π-allyl iron complex. The key allylic alkylation reaction is highly regio- and
- Cooksey, John P.
-
supporting information
p. 5117 - 5126
(2013/08/23)
-
- Relative stereochemical determination and synthesis of the C17-C25 δ-lactone fragment of hemicalide
-
Hemicalide is a novel marine metabolite polyketide distinguished by a unique mechanism of action. Because of insufficient quantities of purified material, this natural product has evaded complete stereochemical assignments. Recently, we have determined th
- Fleury, Etienne,Sorin, Geoffroy,Prost, Elise,Pancrazi, Ange,Sautel, Fran?ois,Massiot, Georges,Lannou, Marie-Isabelle,Ardisson, Janick
-
p. 855 - 864
(2013/04/23)
-
- A novel acid-catalyzed O-benzylating reagent with the smallest unit of imidate structure
-
Formal trimerization of the smallest unit of benzyl imidate leads to 2,4,6-tris(benzyloxy)-1,3,5-triazine (TriBOT), which can be used as an acid-catalyzed O-benzylating reagent. The reaction of various functionalized alcohols with 0.4 equiv of TriBOT in the presence of trifluoromethanesulfonic acid afforded the benzyl ethers in good yields. TriBOT is an inexpensive stable crystalline solid with high atom economy.
- Yamada, Kohei,Fujita, Hikaru,Kunishima, Munetaka
-
p. 5026 - 5029,4
(2012/12/12)
-
- A novel acid-catalyzed O-benzylating reagent with the smallest unit of imidate structure
-
Formal trimerization of the smallest unit of benzyl imidate leads to 2,4,6-tris(benzyloxy)-1,3,5-triazine (TriBOT), which can be used as an acid-catalyzed O-benzylating reagent. The reaction of various functionalized alcohols with 0.4 equiv of TriBOT in the presence of trifluoromethanesulfonic acid afforded the benzyl ethers in good yields. TriBOT is an inexpensive stable crystalline solid with high atom economy.
- Yamada, Kohei,Fujita, Hikaru,Kunishima, Munetaka
-
p. 5026 - 5029
(2013/01/15)
-
- Microwave-assisted benzyl-transfer reactions of commercially available 2-benzyloxy-1-methylpyridinium triflate
-
Benzylation of alcohols and other substrates under thermal conditions translates smoothly from conventional heating into MW-assisted organic synthesis (MAOS). Reactions times are decreased from hours to minutes while good to excellent yields are maintained. MW heating should be considered for benzylation of high-value substrates using the title reagent.
- Wang, Teng-Wei,Intaranukulkit, Tanit,Rosana, Michael R.,Slegeris, Rimantas,Simon, Janet,Dudley, Gregory B.
-
supporting information; experimental part
p. 248 - 250
(2012/02/04)
-
- Efficient synthesis of the C1-C13 fragment of bistramide A
-
Herein we report an efficient synthesis of the C1-C13 fragment of bistramide A from (S)-1,2,4-butanetriol and Roche ester in 14 steps and 13% overall yield. Georg Thieme Verlag Stuttgart - New York.
- Tomas, Loic,Bechet, Thibault,Jeanneau, Erwann,Gueyrard, David,Goekjian, Peter G.
-
scheme or table
p. 215 - 218
(2012/03/26)
-
- Stereocontrolled total synthesis of (+)-concanamycin F: The strategic use of boron-mediated aldol reactions of chiral ketones
-
A highly stereocontrolled total synthesis of the 18-membered macrolide (+)-concanamycin F, a potent inhibitor of vacuolar ATPases, is described that proceeds in 5.8% yield over 26 steps. The three key fragments, C1-C13 vinyl iodide, C14-C22 vinyl stannane
- Paterson, Ian,Steadman Neé Doughty, Victoria A.,McLeod, Malcolm D.,Trieselmann, Thomas
-
supporting information; experimental part
p. 10119 - 10128
(2012/01/14)
-
- Synthesis of a platform to access bistramides and their analogues
-
The platform C14-C40, which can be used to prepare bistramide C and 39-oxobistramide K, was synthesized in 19 steps with an overall yield of 6.2%. Furthermore, the chemoselective reduction of the ketone at C-39 was performed giving an easy access to bistramides A, B, D, K, and L. Finally, the versatility of the synthesis of the C14-C40 fragment can allow the preparation of a large variety of stereoisomers to produce bistramide analogues.
- Commandeur, Malgorzata,Commandeur, Claude,Cossy, Janine
-
supporting information; scheme or table
p. 6018 - 6021
(2011/12/16)
-
- Synthesis of the gymnodimine tetrahydrofuran core through a Ueno-Stork radical cyclization
-
A straightforward access to the C10-C20 skeleton of gymnodimine, incorporating a tetrahydrofuran fragment, is described. The elaboration of the THF moiety is based on a stereocontrolled Ueno-Stork cyclization. A Lewis-acid mediated allylation of the resulting acetal at C13 and a Horner-Wadsworth-Emmons olefination on the ketone at C17 complete the synthesis.
- Toumieux, Sylvestre,Beniazza, Redouane,Desvergnes, Valerie,Araoz, Romulo,Molgo, Jordi,Landais, Yannick
-
supporting information; experimental part
p. 3726 - 3732
(2011/06/27)
-
- Stereoselective synthesis of the C15-C26 fragment of the antitumor agent (-)-dictyostatin
-
The synthesis of the C15-C26 fragment of (-)-dictyostatin is reported in 10 steps and 28% overall yield. The key steps are the two stereoselective sulfoxide-directed processes: a Reformatsky-type reaction and a β-keto sulfoxide reduction.
- Ferreiro-Mederos, Leticia,Vila-Gisbert, Silvia,Urbano, Antonio,Carreno, M. Carmen,Colobert, Franoise
-
supporting information; experimental part
p. 758 - 764
(2011/04/16)
-
- Asymmetric synthesis of (R)-3-hydroxy-2-methylpropanoate ('Roche Ester') and derivatives via biocatalytic C=C-bond reduction
-
Enoate reductases from the 'old yellow enzyme' family were employed for the asymmetric bioreduction of methyl 2-hydroxymethylacrylate and its O-allyl, O-benzyl and O-TBDMS derivatives to furnish (R)-configurated methyl 3-hydroxy-2-methylpropionate products in up to >99% ee Variation of the O-protective group had little influence on the stereoselectivity, but a major impact on the reaction rate.
- Stueckler, Clemens,Winkler, Christoph K.,Bonnekessel, Melanie,Faber, Kurt
-
experimental part
p. 2663 - 2666
(2010/12/25)
-
- Compounds and methods of arylmethylation (benzylation) as protection for alcohol groups during chemical synthesis
-
A process for benzylating an alcohol includes mixing 2-benzyloxy-1-methylpyridinium triflate in an aromatic hydrocarbon solvent having a predetermined boiling point; adding an acid scavenger to the mixture; combining the alcohol to be benzylated with the mixture; reacting the alcohol with the 2-benzyloxy-1-methylpyridinium triflate by heating above ambient temperature to generate the benzylated alcohol; and separating the benzylated alcohol from the mixture.
- -
-
Page/Page column 13; 14
(2010/07/14)
-
- New reagents for the synthesis of arylmethyl ethers and esters
-
This Account chronicles efforts leading up to the development of new arylmethyl transfer (benzylation) reagents for protecting oxygen functional groups under relatively mild and neutral conditions. It begins with an investigation of organosiletanes as surrogate hydroxyl groups, which inspired siletane-functionalized benzyl ethers and forced us to confront the difficulties associated with the synthesis of benzyl ethers. The end result is a new series of neutral oxypyridinium salts for the benzylation of various nucleophilic functional groups under mild conditions. 1 Introduction 2 Tamao-type Oxidation of Strained Organosiletanes 3 p-Siletanylbenzyl (PSB) Protecting Groups 4 2-Benzyloxy-1-methylpyridinium Triflate 5 Friedel-Crafts Reactions and Mechanistic Insights 6 Benzyl Ester Formation 7 Substituted Benzyl Transfer Reagents 8 Conclusions and Outlook. Georg Thieme Verlag Stuttgart New York.
- Albiniak, Philip A.,Dudley, Gregory B.
-
scheme or table
p. 841 - 851
(2010/07/10)
-
- A practical synthesis of the C1-C9 fragment of dictyostatin
-
A stereoselective synthesis of the C1-C9 fragment of (-)-dictyostatin has been achieved by use of a titanium(IV) chloride mediated chelation-controlled Mukaiyama aldol reaction and two modified Horner-Wadsworth-Emmons olefinations (Roush-Masamune and Stil
- Zanato, Chiara,Pignataro, Luca,Hao, Zhongyan,Gennari, Cesare
-
body text
p. 2158 - 2162
(2009/04/04)
-
- Process for total synthesis of pladienolide B and pladienolide D
-
[Problems to be Solved] To provide an effective process for total synthesis of pladienolide B and pladienolide D having excellent anti-tumor activity and to provide useful intermediates in the above-described process. [Measure for Solving the Problem] A process for producing a compound represented by Formula (11): wherein P1, P7, P8, P9 and R1 are the same as defined below, characterized by including reacting a compound represented by Formula (12): wherein P7 means a hydrogen atom or a protecting group for hydroxy group; R1 means a hydrogen atom or a hydroxy group, with a compound represented by Formula (13): wherein P1 means a hydrogen atom or a protecting group for hydroxy group; P8 means a hydrogen atom, an acetyl group or a protecting group for hydroxy group; P9 means a hydrogen atom or a protecting group for hydroxy group; or P8 and P9 may form together a group represented by a formula: wherein R5 means a phenyl group which may have a substituent, in the presence of a catalyst.
- -
-
Page/Page column 33
(2010/11/29)
-
- Total synthesis of the potent antitumor macrolides pladienolide B and D
-
Getting cross: The total syntheses of two pladienolides (see picture), which have prominent antitumor activity based on a unique mechanism of action, have been accomplished, and their absolute configurations were verified. The 12-membered aliphatic macrolide structure was formed by ring-closing metathesis, and the side-chain moiety was coupled to the macrolide by Julia-Kocienski olefination or cross-metathesis. (Chemical Equation Presented).
- Kanada, Regina M.,Itoh, Daisuke,Nagai, Mitsuo,Niijima, Jun,Asai, Naoki,Mizui, Yoshiharu,Abe, Shinya,Kotake, Yoshihiko
-
p. 4350 - 4355
(2008/03/12)
-
- INHIBITORS OF TNFα, PDE4 AND B-RAF, COMPOSITIONS THEREOF AND METHODS OF USE THEREWITH
-
Provided herein are compounds having TNFα and/or PDE4 and/or B-RAF inhibitory activity, and compositions thereof. In particular, provided herein are compounds of the formula (I) and pharmaceutically acceptable salts, solvates, hydrates, clathrates, stereoisomers, polymorphs and prodrugs thereof, wherein Ar, R1, R2, R3, R4, n and Z are as described herein. Further provided herein are methods for treating or preventing various diseases and disorders by administering to a patient one or more TNFα and/or PDE4 and/or B-RAF inhibitors. In particular, provided herein are methods for preventing or treating cancer, inflammatory disorders, cognition and memory disorders and autoimmune disorders, or one or more symptoms thereof by administering to a patient one or more TNFα and/or PDE4 and/or B-RAF inhibitors.
- -
-
Page/Page column 146-147
(2010/11/28)
-
- Total synthesis of khafrefungin using highly stereoselective vinylogous Mukaiyama aldol reaction
-
(Chemical Equation Presented) A convergent total synthesis of khafrefungin was accomplished on the basis of (1) the highly stereoselective TiCl 4-mediated vinylogous Mukaiyama aldol reaction using vinylketene silyl N,O-acetal and (2) syn-select
- Shirokawa, Shin-Ichi,Shinoyama, Mariko,Ooi, Isao,Hosokawa, Seijiro,Nakazaki, Atsuo,Kobayashi, Susumu
-
p. 849 - 852
(2007/10/03)
-
- Mix-and-heat benzylation of alcohols using a bench-stable pyridinium salt
-
2-Benzyloxy-1-methylpyridinium inflate (1) is a stable, neutral organic salt that converts alcohols into benzyl ethers upon warming. The synthesis and reactivity of 1 are described herein. Benzylation of a wide range of alcohols occurs in good to excellent yield.
- Poon, Kevin W. C.,Dudley, Gregory B.
-
p. 3923 - 3927
(2007/10/03)
-
- Studies directed towards the synthesis of antascomicin A: stereoselective synthesis of the C22-C34 fragment of the molecule
-
A stereoselective synthesis of the C22-C34 fragment of the non-immunosuppressive immunophilin-binding natural product, antascomicin A was achieved using d-quinic acid as the starting material and highly stereoselective aldol reactions were employed, as ke
- Chakraborty, Tushar Kanti,Mohan, Bajjuri Krishna,Sreekanth, Midde
-
p. 5003 - 5005
(2007/10/03)
-
- A bench-stable organic salt for the benzylation of alcohols
-
2-Benzyloxy-1-methylpyridinium inflate (Bn-OPT) effects the benzylation of alcohols in the absence of acidic or basic promoters. Solutions of Bn-OPT and primary, secondary, or tertiary alcohols give rise to the corresponding benzyl ethers upon mild heating. Acid scavengers are generally included in the reaction mixture. Bn-OPT is crystalline and bench-stable. Georg Thieme Verlag Stuttgart.
- Poon, Kevin W. C.,House, Sarah E.,Dudley, Gregory B.
-
p. 3142 - 3144
(2007/10/03)
-
- Silanediol inhibitors of angiotensin-converting enzyme. Synthesis and evaluation of four diastereomers of Phe[Si]Ala dipeptide analogues
-
Four stereoisomers of a Phe-Ala silanediol dipeptide mimic have been evaluated as inhibitors of angiotensin-converting enzyme (ACE) and compared to ketone-based inhibitors reported by Almquist et al. One stereogenic center of the isomers was derived from
- Kim, Jaeseung,Hewitt, Gregory,Carroll, Patrick,Sieburth, Scott Mc. N.
-
p. 5781 - 5789
(2007/10/03)
-
- Silanediol peptidomimetics. Evaluation of four diastereomeric ACE inhibitors
-
Four diastereomers of a Phe-Ala peptide mimic incorporating a central silanediol group have been individually prepared and tested as inhibitors of angiotensin-converting enzyme (ACE). Three of the silanediols exhibit levels of inhibition that are similar
- Kim, Jaeseung,Sieburth, Scott McN.
-
p. 2853 - 2856
(2007/10/03)
-
- MACROCYCLIC COMPOUNDS USEFUL AS PHARMACEUTICALS
-
The present invention provides compounds having formula (I), and additionally provides methods for the synthesis thereof and methods for the use thereof in the treatment of various disorders including inflammatory or autoimmune disorders, and disorders involving malignancy or increased angiogenesis, wherein R1 -R11, t, X, Y, Z, and n are as defined herein.
- -
-
Page/Page column 200
(2010/02/07)
-
- Convergent enantioselective synthesis of vinigrol, an architecturally novel diterpenoid with potent platelet aggregation inhibitory and antihypertensive properties. 1. Application of anionic sigmatropy to construction of the octalin substructure
-
The coupling of building blocks 15 and 36e in the presence of MgBr2·OEt2 at 0 °C proceeds with an exo stereoselectivity (3.2:1) considerably more advantageous for the acquisition of carbinol 37e than in the absence of the additive (exo/endo = 1:5.7). The pivotal transformation that sets all of the relevant stereocenters of the cis-octalin 55 is the oxyanionic-accelerated [3,3]-sigmatropic rearrangement of 37e. A salient feature is the structurally enforced adoption of a boatlike transition state that serves to properly set four vicinal methine hydrogens in an all-cis arrangement. The ensuing conversion of 55 into iodo sulfone 62 has permitted X-ray crystallographic confirmation of all absolute stereochemical assignments since the isopropyl substituent was initially installed enantioselectively via the Evans oxazolidinone protocol. No intramolecular anionic cyclization of 62 to generate the tricyclic framework was seen. This absence of reactivity is attributed to conformational factors that inhibit attainment of the proper SN2 reaction trajectory.
- Paquette, Leo A.,Guevel, Ronan,Sakamoto, Shuichi,Kim In Ho,Crawford, Jason
-
p. 6096 - 6107
(2007/10/03)
-
- Chemistry and biology of khafrefungin. Large-scale synthesis, design, and structure-activity relationship of khafrefungin, an antifungal agent
-
Large-scale synthesis, design, and structure-activity relationships of khafrefungin are reported. Khafrefungin is an antifungal agent that inhibits inositol phosphorylceramide (IPC) synthase, a enzyme involved in fungal sphingolipid biosynthesis. Unlike o
- Nakamura, Masayuki,Mori, Yuichiro,Okuyama, Kennichi,Tanikawa, Kunihiro,Yasuda, Satoshi,Kanada, Kentaro,Kobayashi, Shu
-
p. 3362 - 3376
(2007/10/03)
-
- Efficient total synthesis of khafrefungin: Convergent approach using Suzuki coupling under thallium-free conditions toward multigram-scale synthesis
-
An efficient and practical synthetic route to khafrefungin, an antifungal agent, has been developed based on successive coupling of three components, 3, 4, and then 2. A key step of the synthesis is the Suzuki coupling of 2 and 10, in which the use of tox
- Mori, Yuichiro,Nakamura, Masayuki,Wakabayashi, Takeshi,Mori, Kouhei,Kobayashi, Shu
-
p. 601 - 603
(2007/10/03)
-
- A convergent synthesis of (S)-β-methyl-2-aryltryptamine based gonadotropin releasing hormone antagonists
-
A practical synthesis of (S)-β-methyl-2-aryltryptamine based gonadotropin releasing hormone antagonists which features a palladium-catalyzed Larock indole synthesis and a palladium-catalyzed Suzuki-Miyaura sequence to install the 2-position aryl substitue
- Walsh, Thomas F,Toupence, Richard B,Ujjainwalla, Feroze,Young, Jonathan R,Goulet, Mark T
-
p. 5233 - 5241
(2007/10/03)
-
- 6-AZAINDOLE COMPOUNDS AS ANTAGONISTS OF GONADOTROPIN RELEASING HORMONE
-
There are disclosed compounds of formula (I) and pharmaceutically acceptable salts thereof which are useful as antagonists of GnRH and as such may be useful for the treatment of a variety of sex-hormone related and other conditions in both men and women.
- -
-
-
- Antagonists of gonadotropin releasing hormone
-
There are disclosed compounds of formula (I) and pharmaceutically acceptable salts thereof which are useful as antagonists of GnRH and as such may be useful for the treatment of a variety of sex-hormone related and other conditions in both men and women.
- -
-
-
- Antagonists of gonadotropin releasing hormone
-
There are disclosed compounds of formula (I) and pharmaceutically acceptable salts thereof which are useful as antagonists of GnRH and as such may be useful for the treatment of a variety of sex-hormone related and other conditions in both men and women.
- -
-
-
- ANTAGONISTS OF GONADOTROPIN RELEASING HORMONE
-
There are disclosed compounds of formula (I) STR1 and pharmaceutically acceptable salts thereof which are useful as antagonists of GnRH and as such may be useful for the treatment of a variety of sex-hormone related and other conditions in both men and women.
- -
-
-
- Antagonists of gonadotropin releasing hormone
-
There are disclosed compounds of formula (I) STR1 and pharmaceutically acceptable salts thereof which are useful as antagonists of GnRH and as such may be useful for the treatment of a variety of sex-hormone related and other conditions in both men and women.
- -
-
-
- ANTAGONISTS OF GONADOTROPIN RELEASING HORMONE
-
There are disclosed compounds of formula (I) STR1 and pharmaceutically acceptable salts thereof which are useful as antagonists of GnRH and as such may be useful for the treatment of a variety of sex-hormone related and other conditions in both men and wo
- -
-
-
- ANTAGONISTS OF GONADOTROPIN RELEASING HORMONE
-
There are disclosed compounds of formula (I) STR1 and pharmaceutically acceptable salts thereof which are useful as antagonists of GnRH and as such may be useful for the treatment of a variety of sex-hormone related and other conditions in both men and women.
- -
-
-
- Enantioselective total synthesis of altohyrtin C (spongistatin 2)
-
The first total synthesis of a spongipyran macrolide, altohytrin C, is described. The convergent synthesis strategy relies on a regioselective macrolactonization, a stereoselective Wittig coupling of the two major synthetic fragments, a complex anti aldol reaction to join the C1-C15 and C16-C28 spiroketal regions, and an anomeric sulfone acylation to join the C29-C37 and C38-C43 pyran regions. The incorporation of the C44- C51 sidechain in the final stages of the synthesis establishes a viable route for the construction of variants in this pharmacologically important region. Methodological developments en route to the total synthesis include a 1,5 antiselective methyl ketone aldol reaction and a diastereoselective approach to Lewis acid mediated β-C-glycosidation. Completion of the synthesis has confirmed the stereochemical assignments proposed in the altohyrtin series and has established the identity of the altohyrtin and spongistatin marine macrolides.
- Evans, David A.,Trotter, B. Wesley,Coleman, Paul J.,Cote, Bernard,Dias, Luiz Carlos,Rajapakse, Hemaka A.,Tyler, Andrew N.
-
p. 8671 - 8726
(2007/10/03)
-
- Constructing the side-chain of the polyketide herbicide herboxidiene: A protocol for the synthesis of enantiomerically enriched C-11 to C-19 fragments
-
The aldehyde 5, corresponding to the C-11 to C-19 fragment of the polyketide herbicide herboxidiene 1, has been prepared in enantio-enriched form.
- Banwell, Martin G.,Bui, Chinh T.,Hockless, David C. R.,Simpson, Gregory W.
-
p. 1261 - 1263
(2007/10/03)
-