cas 38002-45-8, 3-BROMO-1-(TRIMETHYLSILYL)-1-PROPYNE

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Kinetically Controlled Radical Addition/Elimination Cascade: From Alkynyl Aziridine to Fluorinated Allenes
A kinetically controlled radical addition/elimination reaction generating fluorinated allenes was developed. This strategy offers a route to a facile synthesis of diverse trifluoromethyl, difluoromethylene, and perfluoroalkyl functionalized allenes from readily available fluoroalkyl halides and alkynyl aziridines under visible-light irradiation. Density functional theory calculation of this radical clock type of reaction revealed a kinetically controlled C-N bond cleavage overcoming the alternative thermodynamically controlled C-C bond cleavage process.
Song, Tingting,Zhu, Lei,Li, Haoyu,Tung, Chen-Ho,Lan, Yu,Xu, Zhenghu
p. 2419 - 2424
(2020)
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Low-valent dialkoxytitanium(ii): a useful tool for the synthesis of functionalized seven-membered ring compounds
Herein, we describe unprecedented access to all-carbon or heterocyclic seven-membered ring frameworks from 1,8-ene-ynes promoted by inexpensive low-valent titanium(ii) species, readily available from Ti(OiPr)4and Grignard reagent. A broad range of cycloheptane, azepane or oxepane derivatives has been obtained (19 examples) with moderate to good yields and an excellent selectivity (up to 95/5 d.r.).
Bodinier, Florent,Sanogo, Youssouf,Ardisson, Janick,Lannou, Marie-Isabelle,Sorin, Geoffroy
supporting information
p. 3603 - 3606
(2021/04/14)

Enantioselective Cleavage of Cyclobutanols Through Ir-Catalyzed C?C Bond Activation: Mechanistic and Synthetic Aspects
The Ir-catalyzed conversion of prochiral tert-cyclobutanols to β-methyl-substituted ketones proceeds under comparably mild conditions in toluene (45–110 °C) and is particularly suited for the enantioselective desymmetrization of β-oxy-substituted substrates to give products with a quaternary chirality center with up to 95 % ee using DTBM-SegPhos as a chiral ligand. Deuteration experiments and kinetic isotope effect measurements revealed major mechanistic differences to related RhI-catalyzed transformations. Supported by DFT calculations we propose the initial formation of an IrIII hydride intermediate, which then undergoes a β-C elimination (C?C bond activation) prior to reductive C?H elimination. The computational model also allows the prediction of the stereochemical outcome. The Ir-catalyzed cyclobutanol cleavage is broadly applicable but fails for substrates bearing strongly coordinating groups. The method is of particular value for the stereo-controlled synthesis of substituted chromanes related to the tocopherols and other natural products.
Ratsch, Friederike,Strache, Joss Pepe,Schlundt, Waldemar,Neud?rfl, J?rg-Martin,Adler, Andreas,Aziz, Sarwar,Goldfuss, Bernd,Schmalz, Hans-Günther
supporting information
p. 4640 - 4652
(2021/02/11)

Iron-Catalyzed [2+2+2] Annulation of Aliphatic Bridged 1,n-Enynes with Aldehydes for the Synthesis of Fused Pyrans
An iron-catalyzed [2+2+2] annulation of aliphatic bridged 1,n-enynes with aldehydes was developed. Aldehydes play a dual role as the precursors of acyl radicals to trigger the cascade cyclization but also as the radical acceptors to terminate the annulation. This two-in-one strategy overcomes the limitation in [2+2+m] cyclization that requires a rigid benzene skeleton as the essential linker, thus enabling the efficient synthesis of functionalized fused [5.6] and [6.6] pyran skeletons.
Tian, Tian,Wang, Xin,Lv, Leiyang,Li, Zhiping
supporting information
p. 4425 - 4428
(2020/06/05)

Direct Access to Allenylphosphine Oxides via a Metal Free Coupling of Propargylic Substrates with P(O)H Compounds
A direct and convenient approach for the coupling of propargylic substrates with diphenylphosphine oxide in the presence of Tf2O and 2,6-lutidine has been developed. The method provides a general approach for the construction of attractive allenylphosphoryl skeletons with high atom and step economy under metal free conditions.
Yang, Chun-Hua,Fan, Huihui,Li, Huimin,Hou, Shenyin,Sun, Xiangkun,Luo, Donghao,Zhang, Yinchao,Yang, Zhantao,Chang, Junbiao
p. 9438 - 9441
(2019/11/20)

SYNTHETIC RETINOIDS (IN CELL MODULATION)
There are described novel compounds of formula I: (I) in which, in which A1, A2, A3, A4, R1 and R2 are each as herein defined, for use in the treatment or alleviation of an RAR mediated condition; and methods related thereto.
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Page/Page column 51; 52

(2018/03/06)

A cyclization-rearrangement cascade for the synthesis of structurally complex chiral gold(I)-aminocarbene complexes
A facile synthesis of chiral cyclic alkyl aminocarbene-gold(I) complexes from gold-free 1,7-enyne substrates was developed. The novel cyclization-rearrangement reaction sequence is triggered by the addition of (Me2S)AuCl to different 1,7-enynes and leads to structurally unique carbene-gold(I) complexes in high yields. These novel complexes are catalytically active and inhibit the proliferation of different human cancer cell lines.
Kolundzic, Filip,Murali, Annamalai,Perez-Galan, Patricia,Bauer, Jonathan O.,Strohmann, Carsten,Kumar, Kamal,Waldmann, Herbert
supporting information
p. 8122 - 8126
(2014/08/18)

Studies towards the identification of the sex pheromone of Thyrinteina arnobia
The eucalyptus brown-looper Thyrinteina arnobia (Lepidoptera: Geometridae) is considered an important pest in Brazilian native plants, e.g. Psidium guajava, and exotic plants, such as Eucalyptus species. In this work we describe the isolation of the pheromone components of T. arnobia, using glands extract and solid phase micro extraction (SPME) of virgin females. The samples were analyzed by gas chromatography with an electroantennographic detector (GC-EAD), and mass spectrometry (GC-MS). Two reproducible electroantennographic responses were elicited in the male antenna of T. arnobia and one of them was identified as 3,4-epoxy-6,9-heneicosadiene by CG-MS. The racemic synthesis of this epoxydiene was carried out in 10 steps and 28percent overall yield. The four stereoisomers of the epoxydiene were also synthesized employing the corresponding enantiomeric enriched epoxyalcohols.
Moreira, Jardel A.,Neppe, Tiago,De Paiva, Marcelo M.,Deobald, Anna M.,Batista-Pereira, Luciane G.,Paixa?o, Marcio W.,Corre?a, Arlene G.
p. 1933 - 1941
(2014/01/06)

Bifunctional iron complexes: Efficient catalysts for C=O and C=N reduction in water
The application of bifunctional iron complexes for the hydrogenation of polarized C=X bonds is reported. Two modified Knoelker complexes bearing ionic fragments were synthesized and fully characterized. With these well-defined complexes, the reaction proceeded under mild conditions in pure water, and various alcohols and amines were isolated in good yields. Compared with hydrogenation in organic solvents, better reactivities were observed. Is this the iron age? Well-defined iron-complex-catalyzed reduction of aldehydes, ketones, and imines using molecular hydrogen in water is presented. Under mild conditions, good yields for a broad range of substrates are achieved.
Merel, Delphine S.,Elie, Margaux,Lohier, Jean-Francois,Gaillard, Sylvain,Renaud, Jean-Luc
p. 2939 - 2945
(2013/10/21)

ROMP copolymers for orthogonal click functionalizations
The ring-opening metathesis polymerization using ruthenium carbene initiators developed by Grubbs et al. is one of the most functional group tolerant living polymerization methods known. One of the most used postpolymerization functionalization methods used today is the copper-catalyzed 1,3-dipolar cycloaddition between alkynes and organic azides. Organic azides are, however, not tolerated by ruthenium carbene initiators, and nonprotected alkynes have been shown to slow down the propagation reaction or react with the propagating species leading to broad molecular weight distributions. Here we report the copolymer synthesis of three orthogonally functionalizable monomers: one carrying an activated pentafluorophenyl ester, one a maleimide unit, and a third one a trialkylsilyl-protected alkyne. From these monomers, statistical terpolymers as well as diblock copolymers were synthesized with different molecular weights and monomer compositions or block ratios, respectively. Excellent control over molecular weight and molecular weight distribution could be achieved using Grubbs' first-generation ruthenium carbene initiator. Herein we present the synthesis and orthogonal triple postpolymerization functionalization of these copolymers.
Schaefer, Mark,Hanik, Nils,Kilbinger, Andreas F. M.
p. 6807 - 6818
(2012/11/07)

Lactone radical cyclizations and cyclization cascades mediated by SmI 2-H2O
Unsaturated lactones undergo reductive radical cyclizations upon treatment with SmI2-H2O to give decorated cycloheptanes in a single highly selective operation during which up to three contiguous stereocenters are generated. Furthermore, cascade processes involving lactones bearing two alkenes, an alkene and an alkyne, or an allene and an alkene allow "one-pot" access to biologically significant molecular scaffolds with the construction of up to four contiguous stereocenters. The cyclizations proceed by the trapping of radical anions formed by electron transfer reduction of the lactone carbonyl.
Parmar, Dixit,Matsubara, Hiroshi,Price, Kieran,Spain, Malcolm,Procter, David J.
supporting information; experimental part
p. 12751 - 12757
(2012/09/05)

Carboxylate-directed tandem functionalisations of α,β- dihaloalkenoic acids with 1-alkynes: A straightforward access to (Z)-configured, α,β-substituted γ-alkylidenebutenolides
An easy and mild copper(I)-catalysed lactonisation of readily available (E)-2,3-dihalopropenoic acid derivatives regio- and stereoselectively leads to rarely described (Z)-3-halo-5-ylidene-5H-furan-2-ones. These compounds are subsequently able to undergo classical Pd-catalysed cross-coupling reactions, providing 3-substituted and 3,4-disubstituted 5-ylidene-5H-furan-2-ones (see scheme).
Inack Ngi, Samuel,Cherry, Khalil,Héran, Virginie,Commeiras, Laurent,Parrain, Jean-Luc,Duchêne, Alain,Abarbri, Mohamed,Thibonnet, Jér?me
supporting information; experimental part
p. 13692 - 13696
(2012/01/06)

Efficient synthesis of nevirapine analogs to study its metabolic profile by click fishing
Knowledge of the biotransformation and pharmacokinetics of the antiretroviral agent nevirapine is still insufficient. In order to trace rash inducing metabolites of nevirapine, we devised a short and efficient multi-gram synthesis of a nevirapine analog that can be coupled to azide containing compounds by click chemistry.
Bernard, Sylvain,Defoy, Daniel,Dory, Yves L.,Klarskov, Klaus
supporting information; experimental part
p. 6127 - 6130
(2010/06/13)

Asymmetric synthesis of α-allenylglycines
The coupling of the homocuprate of the bislactim ether of cyclo-(-L-Val-Gly-) (9) with primary propargyl halides produces the allenyl-substituted bislactim ethers 11 in a highly diastereoselective manner, whereas the alkylation of the lith-iated bislactim ether of cyclo-(-L-Val-Gly-) yields the proparg-yl-substituted bislactim ethers 12. Subsequent hydrolysis affords, after protection of the amino group, the methyl α- allenylglycinates 15, the α-allenylglycines 16, and the methyl α-propargylglycinates 17.
Bucuroaia, Carmen,Groth, Ulrich,Huhn, Thomas,Klinge, Michael
experimental part
p. 3605 - 3612
(2009/12/01)

Regioselective allene synthesis and propargylations with propargyl diethanolamine boronates
"Chemical Equation Presented" The utility of propargyl diethanolamine boronates as reagents for the preparation of allenes and homopropargylic alcohols is presented. Protonolysis with TFA and electrophilic substitution with N-halosuccinimides proceeded wi
Fandrick, Daniel R.,Reeves, Jonathan T.,Tan, Zhulin,Lee, Heewon,Song, Jinhua J.,Yee, Nathan K.,Senanayake, Chris H.
scheme or table
p. 5458 - 5461
(2010/03/01)

A facile and regioselective synthesis of 2,5-disubstituted pyrroles via gold-catalyzed cycloisomerization of acetylenylaziridines
Gold-catalyzed cycloisomerization reaction of acetylenylaziridines provides 2,5-disubstituted pyrroles in high yields. The presence of protic species accelerates the reaction rate and improves the yields of pyrrole products.
Chen, Dong-Dong,Hou, Xue-Long,Dai, Li-Xin
supporting information; scheme or table
p. 6944 - 6946
(2010/02/27)

Facile construction of spirocyclopropanated bi-, tri- and tetracyclic skeletons by novel cascades involving intra- and intermolecular heck reactions of 2-bromo-1,6-enynes and bicyclopropylidene
Acyclic 2-bromo-1,6-enynes 5-R, 9-R and 11-R with bulky substituents at the acetylenic terminus were co-cyclized with the highly strained bicyclopropylidene (12) under palladium catalysis at 80 °C to give the cross-conjugated tetraenes 13-R, 18-R and 19-R in moderate-to-good yields (34-71%). Only the co-cyclization of 5-Ph gave rise to an additional product, which was identified as the 11-membered ring 20. At elevated temperatures (120-140 °C) the initially formed tetraenes underwent 6π- electrocyclization to give spiro[cyclopropane-1,4′-bicylo[4.3.0]-1(6),2- dienes] 21-R, 22-R and 23-R. This novel class of spirocyclopropanated oligocycles is also accessible by a one-pot protocol. The highest yields for both the tetraenes and bicyclo[4.3.0]nonadiene and its heteroanalogues were obtained with bulky substituents at the alkyne terminus of the precursors. Heteroatom-containing precursors 9-R and H-R gave lower yields than their all-carbon analogues 5-R. The acyclic 2-bromo-1,8-dien-6-ynes 28a,b,c upon palladium-catalyzed co-cyclization with bicyclopropylidene (12) at 110 °C gave spirocyclopropanated tricycles 31a,b and 32, respectively, in moderate yields (14, 31 and 32%). These products were formed by two consecutive 6π-electrocyclizations. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005.
Schelper, Michael,De Meijere, Armin
p. 582 - 592
(2007/10/03)

Rhodium(l)-catalyzed carbonyl allenylation versus propargylation via redox transmetalation across tetragonal tin(ll) oxide
A reagent combination of β-SnO and catalytic [Rh(COD)Cl]2 in THF-H2O promotes the reaction of propargyl bromides and aldehydes and directs the regioselectivity toward the formation of either allenic alcohols or homopropargylic alcohols. This highly regioselective either/or transformation proceeds via a transmetalation from rhodium to tin, in which metallotropic rearrangement between a propargylmetal and allenylmetal is arrested.
Banerjee, Moloy,Roy, Sujit
p. 2137 - 2140
(2007/10/03)

Synthetic studies toward bioactive cyclic peroxides from the marine sponge Plakortis angulospiculatus
(formula presented) The total synthesis of two stereoisomers of a bioactive cyclic peroxide isolated from the marine sponge Plakortis angulospiculatus has been achieved in 18 steps with an overall yield of 2.8%. Diels-Alder addition of singlet oxygen to an acyclic triene carboxylic acid precursor was used to construct the 3,6-dihydro-1,2-dioxin ring. By comparing spectral data of the synthesized compounds and the natural material, we tentatively assign the absolute stereochemistry for the natural product as 3S,6R,8S,10R.
Yao, Gang,Steliou, Kosta
p. 485 - 488
(2007/10/03)

The aza-[2,3]-Wittig sigmatropic rearrangement of acyclic amines: Scope and limitations of silicon assistance
The inclusion of a C-2 trialkylsilyl substituent into allylic amine precursors allows the base-induced aza-[2,3]-Wittig sigmatropic rearrangement to proceed in excellent yield and diastereoselectivity. The rearrangement precursors require a carbonyl-based nitrogen protecting group that must be stable to excess of strong base required for the reaction. The N-Boc and N-benzoyl group are very good at stabilizing the product anion and initiating deprotonation. The migrating groups (G) need to stabilize the intial anion by resonance and require G-CH3 pKa > 22 in order for the initial anion to be reactive enough for rearrangement. Products 7, 29b-d,f,g, and 23 are formed with high (10-20:1) anti diastereoselectivity. Product 23 containing the morpholine amide group is useful for preparing other carbonyl derivatives.
Anderson,Flaherty,Swarbrick
p. 9152 - 9156
(2007/10/03)

Stereochemical control in the metallohalocarbenoid route to linear enediynes
Methods for the stereoselective preparation and unmasking of disubstituted Z enediynes are reported. The origins of the unprecedented stereoselectivity of the process are uncovered.
Wright, Justin M.,Jones, Graham B.
p. 7605 - 7609
(2007/10/03)

Titanium(II)-based Z-reduction of alkynes. Syntheses of deuterium labelled linolenic and oleic acids and (3E,8Z,11Z)-tetradeca-3,8,11-trienyl acetate, the sex pheromone of a tomato pest, Scrobipalpuloides absoluta
An operationally simple TiII-mediated, stereo- and regio-specific reduction of isolated, conjugated and methylene 'skipped' polyynes to the corresponding Z-polyenes in a one-pot procedure is described and applied inter alia to the syntheses of deuterium labelled linolenic and oleic acids. Final quenching with D2O (instead of H2O) results in regio- and stereo-specific Z-dideuteration of the alkyne. The synthesis of (3E,8Z,11Z)-tetradeca-3,8,11-trienyl acetate, the major sex pheromone of Scrobipalpuloides absoluta, a destructive pest of tomatoes, and the (3Z,8Z,11Z)-isomer, utilises this methodology in key reduction steps, and under- or over-reduction are negligible.
Hungerford, Natasha L.,Kitching, William
p. 1839 - 1858
(2007/10/03)

Stereoselective synthesis of new hetero(P, Si, Ge, Sn)cyclic derivatives from zirconium diyne and diene complexes
The dipropargylic derivatives of Si, Ge, P, 1a-c, react with the zirconocene entity 'Cp2Zr' and give the intermediate bicyclocomplexes 2a-c characterized by 1H and 31P-NMR. The electrophilic addition of H+, Br2 leads to the corresponding exo dienic metallacyclopentanes 3,4. The cyclozirconation reaction with hetero-diallylic compounds 5a-d gives the metallacyclopentanes 7-15, after reaction with different electrophiles such as H+, PCl3, PhPCl2, Ph2PCl or Ph2PCl(BH3), Br2. The cyclozirconation reaction of diynes is stereoselective and leads to the E,E-exocyclic dienes whereas the selectivity of cyclozirconation of dienes depends on the substituents on the heteroatom.
Mirza-Aghayan, Maryam,Boukherroub, Rabah,Oba, Gabriel,Manuel, Georges,Koenig, Max
p. 61 - 70
(2007/10/03)

7-Silylcamptothecins (silatecans): A new family of camptothecin antitumor agents
The synthesis and biological evaluation of about one dozen 7-silylcamptothecin derivatives are described. Most new compounds show potencies comparable to or better than camptothecin itself. The best compound, 11-fluoro-10-amino-7-trimethylsilylcamptothecin, is more than 20 times more potent than camptothecin in cell assays.
Josien, Hubert,David, Bom,Curran, Dennis P.,Zheng, Yu-Huang,Chou, Ting-Chao
p. 3189 - 3194
(2007/10/03)

Convergent synthetic routes to orthogonally fused conjugated oligomers directed toward molecular scale electronic device applications
This paper describes the synthetic organic phase of a project directed toward the construction of molecular scale electronic devices. Outlined is a convergent synthetic route to orthogonally fused conjugated organic oligomers. The final systems are to have a potentially conducting chain fused perpendicularly to a second potentially conducting chain via a a bonded network. One of the core segments synthesized is based on a spirobithiophene moiety with a central silicon atom. It is formed by a zirconium-promoted bis(bicyclization) of a tetrapropargylsilane. The second core is a 9,9′-spirobifluorene system. Terminal halide groups provide the linkage points for further extension of the chains via Pd-catalyzed or Pd/Cu-catalyzed cross coupling methods. All four branching arms are affixed to the core in a single operation, thus making the syntheses highly convergent. In the cases of the larger functionalized systems, alkyl substituents on the thiophenes afford soluble materials. In order to prepare the molecules with > 50 A lengths, an iterative divergent/convergent approach had to be utilized for the construction of oligo(thiophene-ethynylene) branching arms. Organopalladium-catalyzed procedures are used extensively for the syntheses of the orthogonally fused compounds.
Wu, Ruilian,Schumm, Jeffry S.,Pearson, Darren L.,Tour, James M.
p. 6906 - 6921
(2007/10/03)

N-Alkenyl nitrone dipolar cycloaddition routes to piperidines and indolizidines. Part 8. The scope of tandem reactions involving hydroxylamine-alkyne cyclisations
A tandem sequence of hydroxylamine-alkyne cyclisation/1,3-dipolar cycloaddition, provides useful entry into tricyclic systems of type 4. The scope of such reactions is explored in this paper. A novel cascade cyclisation of N-hydroxypyrrolidines of type 26 and 28 involving hydroxylamine-alkyne cyclisation, Cope elimination and 1,3-dipolar cycloaddition is also reported.
Davison, Edwin C.,Forbes, Ian T.,Holmes, Andrew B.,Warner, Jacqueline A.
p. 11601 - 11624
(2007/10/03)

The synthesis of substituted pyrrolidines by a samarium (II) iodide mediated ring closure. Part 2
Samarium (II) iodide-mediated ring closures, of substituted N-propargyl substrates derived from L-serine, have been used to generate a series of 2,3,4-trisubstituted pyrrolidine derivatives.
Baldwin, Jack E.,MacKenzie Turner, Sean C.,Moloney, Mark G.
p. 9425 - 9438
(2007/10/02)

Total synthesis of (10Z,13Z,16Z)-nonadeca-10,13,16,18-tetraen-1-ol
The title compound is obtained by successive couplings between propargylic bromides and alkynes, which are catalyzed by cuprous salts.Key Words: 1-4 diyne / coupling / hydroboration / Z,Z,Z-triene
Crousse, B.,Pichon, O.,Soulie, J.
p. 154 - 159
(2007/10/02)

An Efficient Stereocontrolled Synthesis of 12(R)-HETE and 12(S)-HETE
An efficient synthesis of 12(R) and 12(S) HETEs was realized by assembly of the easily obtainable synthons: optically pure iodo-alcohols 3(R) and 3(S) with the ester 4, followed by reduction with activated zinc.
Chemin, Denis,Gueugnot, Sylvie,Linstrumelle, Gerard
p. 4369 - 4378
(2007/10/02)

Novel anti-inflammatory agents, pharmaceutical compositions and methods for reducing inflammation
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(2008/06/13)

SYNTHESIS AND ELECTROPHILIC SUBSTITUTION REACTIONS OF 1,3-DISUBSTITUTED PROPYNES CONTAINING GROUP-IVB ELEMENTS
The reaction of trialkylstannyldialkylamines and trialkylstannylpropadienes produces 1,3-bis(trialkylstannyl)propynes in high yield. 1,3-Bistrialkylsilyl(germyl)propynes and also certain 1,3-bis(trialkylstannyl)propynes can be obtained by the organomagnesium method.During the bromination of 1,3-bis(trialkylsilyl)(trialkylgermyl)propynes, the E-CH2Csp bond is preferentially split.In contrast to these, 1,3-bis(trialkylstannyl)propynes may undergo a bromodestannylation reaction at the Sn-Csp bond with the formation of 1-bromo-3-trialkylstannyl-1-propynes. 1,3-Bis(trialkylstannyl)propynes react with halosilanes with the formation of acetylene compounds only, whereby the variation of the nature of the silane and the structure of stannylpropyne enables selective splitting of the Sn-Csp or Sn-CH2Csp bond.
Bogoradovskii, E. T.,Zavgorodnii, V. S.,Liepin'sh, E. E.,Birgele, I. S.,Petrov, A. A.
p. 1295 - 1306
(2007/10/02)

Hydroquinoline compounds, compositions containing same and processes for preparing same
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(2008/06/13)

Silane compound for use in the synthesis of semiconducting polymers with perpendicular arranged cores
The stereochemical structure necessary for preparation of perpendicularly arranged cores is provided by a compound of the formula STR1 wherein X is a reactive group through which polymeric subunits can be bonded to the compound. In particular, X is advantageously Br. This compound can be synthesized by the reaction of tetrakis(3'-trimethylsilyl-2'-propynyl)silane with zirconocene dichloride and n-butyllithium and adding sulfur monochloride to the reaction product. This produces an adduct in which X is SiMe3. This adduct may be converted to the bromo compound by reaction with bromine. The tetrakis(3'-trimethylsilyl-2-propynyl)silane may be prepared by forming a magnesium Grignard reagent from 3-bromo-1-trimethylsilylpropyne and reacting the Grignard reagent with silicon tetrachloride.
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(2008/06/13)

Benzimidazolyl-sulfinyl-tetrahydroquinolines
A hydroquinoline compound of the formula (1): STR1 wherein R1, R2, R3, A, l, m and n are as defined or its pharmaceutically acceptable salt, composition containing the compound and processes for preparing same are disclosed. The compound is useful as an antiulcer agent.
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(2008/06/13)

Trimethylsilylation of Propargyl Chloride and Propargyl Bromide
Me3SiCCCH2Cl and Me3SiCCCH2Br are obtained in high yields by treating propargyl chloride and bromide, respectively, with n-butyllithium and lithium diisopropylamide and subsequently adding chlorotrimethylsilane in the presence of hexamethylphosphoric triamide (HMPT).An effective method for the purification of HMPT is described.
Verkruijsse, H.D.,Brandsma, L.
p. 3375 - 3378
(2007/10/02)

Novel anti-inflammatory agents, pharmaceutical compositions and methods for reducing inflammation
The present invention relates to novel specifically-substituted phenyl compounds, especially substituted di-tert-butyl phenol derivatives, which are effective as anti-inflammatory, analgesic and/or antipyretic agents. These phenyl compounds are substituted with a low molecular weight alkyl chain which terminates in a specific unsaturated functional group. These unsaturated functionalities are --C CH, C=CH2, C=C=CH2, and aldehydes in the form of their acetals. The present invention further relates to pharmaceutical compositions which contain an anti-inflammatory agent of the present invention and a pharmaceutically-acceptable carrier. Finally, the present invention relates to methods for treating diseases characterized by inflammation, such as rheumatoid arthritis and osteoarthritis, in humans or lower animals. Such methods comprise administering to a human or lower animal in need of such treatment a safe and effective amount of an anti-inflammatory agent or composition of the present invention.
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(2008/06/13)

Electron Delocalisation and Stabilisation in Substituted Amino- and Hydroxypropynyl Radicals
A series of aminopropynes, RCCCH2NH2 (R = H, Me, t-Bu, Me3Si), RCCCH2N(SiMe3)2, and hydroxypropynes RCCCH2OH (R = H, Me, t-Bu, Me3Si, CF3, and EtO2C), were prepared and the corresponding α-aminopropynyl and α-hydroxypropynyl radicals were examined by e.s.r. spectroscopy.For the first series, the C-N bond rotation barriers were determined from the exchange broadening in the spectra and hence radical stabilization energies were estimated.The spin distribution in these series indicated an extra delocalisation in radicals with captodative substitution.
MacInnes, Iain,Walton, John C.
p. 1077 - 1082
(2007/10/02)

New Synthetic Applications of (Bromozinco)-acetonitrile (BrZnCH2CN)
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Orsini, F.
p. 500 - 503
(2007/10/02)

Inhibition of Renin by Substrate Analogue Inhibitors Containing the Olefinic Amino Acid 5(S)-Amino-7-methyl-3(E)-octenoic Acid
The olefinic dipeptide 5(S)-amino-7-methyl-3(E)-octenoic acid (1) was synthesized and used to make the olefinic peptides LeuψGly-Val-Phe-OCH3 (2) and His-LeuψGly-Val-Phe-OCH3 (3). These olefinic peptides were found to exhibit renin inhibitory activity against both hog kidney renin and human amniotic renin that was comparable to the substrate analogue inhibitors Leu-Leu-Val-Phe-OCH3 and His-Leu-Leu-Val-Phe-OCH3
Johnson, Rodney L.
p. 1351 - 1354
(2007/10/02)

ORGANOMETALLIC COMPOUNDS OF ZINC AS SELECTIVE NUCLEOPHILIC REAGENTS IN ORGANIC SYNTHESIS
The ability of the Reformatsky reagent BrZnCH2CO2tBu 1 to undergo substitution reactions has been verified with several substituted bromides.
Orsini, F.,Pelizzoni, F.
p. 805 - 816
(2007/10/02)

On the Double Bond Isostere of the Peptide Bond: Preparation of an Enkephalin Analogue
Methodology for preparing dipeptide analogues in which a carbon -carbon double bond replaces the normal amide bond is described.Thus, the protected tyrosylglycine analogue, (S)-trans-5-t-butyloxycarbonylamino-6-(4-t-butoxyphenyl)hex-3-enoic acid has been synthesised and incorporated into the Leu-enkephalin analogue (3) by condensation with glycylphenylalanyl-leucine.The enkephalin analogue retained biological activity.The significance of this isosteric replacement of the amide group is discussed.
Hann, Michael M.,Sammes, Peter G.,Kennewell, Peter D.,Taylor, John B.
p. 307 - 314
(2007/10/02)

A Vinylsilane Route of (+/-)-Gymnomitrol
Gymnomitrol, a sesquiterpenic alcohol of unusual structure, has been synthesized in an efficient and stereoselective manner.Selective ketalization of the bicyclooctanedione (4), followed by Wolf-Kishner reduction and deketalization, afforded the Cs symmetric ketone 5.Methylenation with paraformaldehyde and N-methylanilinium trifluoroacetate gave the exocyclic methylene derivative (6) which entered into copper-catalyzed 1,4 addition with the Grignard reagent from (E)-2-(bromovinyl)trimethylsilane and subsequent in situ methylation to deliver 12 in 66percent yield.Epoxidation and dilute acid hydrolysis of this intermediate furnished hydroxy ketone 15 directly.The coproducts 14a and 14b could also be converted to 15 which was oxidized to diketone 16.The final stages of the synthesis involved regioselective addition of methyllithium to 16, dehydration of the tertiary carbinol fuctionality, and ultimate lithium aluminium hydride reduction.
Paquette, Leo A.,Han, Yeun-Kwei
p. 1831 - 1835
(2007/10/02)