896-32-2Relevant academic research and scientific papers
2,2,2-Triphenylethanol: a Hydrogen-Bonded Tetramer Based upon a Centrosymmetric R44(8) Motif
Ferguson, George,Glidewell, Christopher,Zakaria, Choudhury M.
, p. 928 - 931 (1994)
2,2,2-Triphenylethanol, C20H18O, crystallizes as hydrogen-bonded tetrameric aggregates which are centrosymmetric.The resulting planar O4 ring is almost square with O...O distances of 2.786(2) and 2.822(2) Angstroem; the hydroxyl H atoms are fully ordered,
Highly efficient and chemoselective zinc-catalyzed hydrosilylation of esters under mild conditions
Kovalenko, Oleksandr O.,Adolfsson, Hans
supporting information, p. 2785 - 2788 (2015/02/05)
A mild and highly efficient catalytic hydrosilylation protocol for room-temperature ester reductions has been developed using diethylzinc as the catalyst. The methodology is operationally simple, displays high functional group tolerance and provides for a facile access to a broad range of different alcohols in excellent yields.
First selective CYP11B1 inhibitors for the treatment of cortisol-dependent diseases
Hille, Ulrike E.,Zimmer, Christina,Vock, Carsten A.,Hartmann, Rolf W.
supporting information; experimental part, p. 2 - 6 (2011/04/17)
Outgoing from an etomidate-based design concept, we succeeded in the development of a series of highly active and selective inhibitors of CYP11B1, the key enzyme of cortisol biosynthesis, as potential drugs for the treatment of Cushing's syndrome and rela
Gold-catalyzed double migration-benzannulation cascade toward naphthalenes
Dudnik, Alexander S.,Schwier, Todd,Gevorgyan, Vladimir
supporting information; body text, p. 1465 - 1468 (2009/04/10)
(Chemical Equation Presented) A novel gold(I)-catalyzed cycloisomerization of propargylic esters leading to unsymmetrically substituted naphthalenes has been developed. This cascade reaction involves an unprecedented tandem sequence of 1,3- and 1,2-migration of two different migrating groups. It is believed that this transformation likely proceeds via the formation of 1,3-diene intermediate or its precursor, which upon cyclization and aromatization steps transforms into the naphthalene core. 2008 American Chemical Society.
Enantioselective TADMAP-catalyzed carboxyl migration reactions for the synthesis of stereogenic quaternary carbon
Shaw, Scott A.,Aleman, Pedro,Christy, Justin,Kampf, Jeff W.,Va, Porino,Vedejs, Edwin
, p. 925 - 934 (2007/10/03)
The chiral, nucleophilic catalyst TADMAP [1, 3-(2,2,2-triphenyl-1- acetoxyethyl)-4-(dimethylamino)-pyridine] has been prepared from 3-lithio-4-(dimethylamino)pyridine (5) and triphenylacetaldehyde (3), followed by acylation and resolution. TADMAP catalyzes the carboxyl migration of oxazolyl, furanyl, and benzofuranyl enol carbonates with good to excellent levels of enantioselection. The oxazole reactions are especially efficient and are used to prepare chiral lactams (23) and lactones (30) containing a quaternary asymmetric carbon. TADMAP-catalyzed carboxyl migrations in the indole series are relatively slow and proceed with inconsistent enantioselectivity. Modeling studies (B3LYP/6-31G*) have been used in qualitative correlations of catalyst conformation, reactivity, and enantioselectivity.
Fragmentation of 2,2,2-triphenylethoxychlorocarbene: Evidence for ultrafast fragmentation-rearrangement in excited diazirines
Fu, Xiaolin,Moss, Robert A.,Piotrowiak, Piotr,Myahkostupov, Mykhaylo,Gould, Ian R.
, p. 4807 - 4809 (2007/10/03)
(Chemical Equation Presented) Photolysis of 3-(2,2,2-triphenylethoxy)-3- chlorodiazirine gives 2,2,2-triphenylethoxychlorocarbene which fragments with 1,2-phenyl migration and loss of CO and Cl- to yield the 1,1,2-triphenylethyl cation and thence 1,1,2-triphenylethene by proton loss. However, ps and fs laser flash photolysis provides evidence that up to 25% of the alkene product stems from carbocation that arises directly from excited diazirine rather than from the carbene.
DUTPASE INHIBITORS
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Page/Page column 51, (2008/06/13)
Deoxyuridine derivatives of the formula (I) where R1 is H or various substituents; D is -NHCO-, -CONH-, -0-, -C(=O)-, -CH=CH, -CΞC-, -NR5-; R4 is hydrogen or various substituents; R5 is H, C1-C4 alkyl, C1-C4 alkanoyl; E is Si or C; R6, R7 and R8 are independently selected from C1-C8 alkyl, C2-C8 alkenyl, C2-C8 alkynyl or a stable monocyclic, bicyclic or tricyclic ring system; G is -O-, -S-, -CHR10-, -C(=O)-; J is -CH2-, or when G is CHR10 may also be -O- or -NH-; R10 is H, F, -CH3, -CH2NH2, -CH2OH; -OH R11 is H, F, -CH3, -CH2 NH2, -CH2OH, CH(OH)CH3, CH(NH3)CH3; or R10 and R11 together define an olefinic bond, or together form a -CH2-group, thereby defining a cis or trans cyclopropyl group; have utility in the prophylaxis or treatment of protozoal diseases such as malaria.
Development of Chiral Nucleophilic Pyridine Catalysts: Applications in Asymmetric Quaternary Carbon Synthesis
Shaw, Scott A.,Aleman, Pedro,Vedejs, Edwin
, p. 13368 - 13369 (2007/10/03)
TADMAP (1a), a new chiral DMAP catalyst, has been designed to place a C(3)-benzylic trityl group over one face of the pyridine ring, while a C(3)-benzylic acetoxy group creates a chirotopic environment on the other face. TADMAP was prepared in four steps
Asymmetric Synthesis Properties of Sulfinimines (Thiooxime S-Oxides)
Davis, Franklin A.,Reddy, Rajarathnam E.,Szewczyk, Joanna M.,Reddy, G. Venkat,Portonovo, Padma S.,Zhang, Huiming,Fanelli, Dean,Reddy, R. Thimma,Zhou, Ping,Carroll, Patrick J.
, p. 2555 - 2563 (2007/10/03)
Enantiomerically pure sulfinimines (thiooxime S-oxides 10), important building blocks in the asymmetric synthesis of amine derivatives, are prepared in good to excellent yields in one step from aromatic, heteroaromatic, and aliphatic aldehydes. This protocol involves treating commercially available (R)- or (S)-menthyl p-toluenesufinate (Andersen reagent 4) with LiHMDS, followed by the aldehyde, affording (E)-10 exclusively. The sulfinimines 10 are formed via a Peterson-type olefination reaction of silylsulfinamide anion 13 with the aldehyde. Anion 13 is generated by reaction of lithium menthoxide (12a) with bis(trimethylsilyl)sulfinamide 11, which is formed in the reaction of 4 with LiHMDS. The other product formed is O-(trimethylsilyl)menthol (12c), which is isolated in >80% yield for recycling. Two other less efficient methods for the asymmetric synthesis of 10 are discussed: (i) the asymmetric oxidation of sulfenimines 6 with chiral nonracemic oxaziridines and (ii) the reaction of metal aldimines, prepared from nitriles, with 4. All of these protocols fail with ketones.
1-dethia-2-thia-cephalosporanic acids
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, (2008/06/13)
Novel 1-dethia-2-thia-cephalosporanic acid derivatives of the formula STR1 wherein R is selected from the group consisting of STR2 Ra is an organic radical, Ri and Rj are individually selected from the group consisting of hydrogen, aliphatic, aromatic and heterocycle or taken together with the nitrogen atom to which they are attached form an optionally substituted cycle or Rb NH--, Rb is optionally substituted carbocyclic or heterocyclic aryl, R1 and --COM are as defined in the specification, R4 is hydrogen or methoxy, n2 is 0, 1 or 2 and their non-toxic, pharmaceutically acceptable acid addition salts in racemic or optically active form having antibiotic activity and their preparation and novel intermediates.
