52428-02-1Relevant articles and documents
Novel sst4-Selective Somatostatin (SRIF) Agonists. 2. Analogues with β-Methyl-3-(2-naphthyl)alanine Substitutions at Position 8
Erchegyi, Judit,Penke, Botond,Simon, Lajos,Michaelson, Scott,Wenger, Sandra,Waser, Beatrice,Cescato, Renzo,Schaer, Jean-Claude,Reubi, Jean Claude,Rivier, Jean
, p. 5587 - 5596 (2003)
We present a family of human sst4-selective, high-affinity (IC50 = 2-4 nM) cyclic somatostatin (SRIF) octapeptides. These peptides result from the substitution of DTrp8 in H-c[Cys 3-Phe6-Phe7-DTrp8-Lys 9-Thr10-Phe11-Cys14]-OH (SRIF numbering) (ODT-8) by one of the four conformationally biased stereoisomers of β-methyl-3-(2-naphthyl)alanine (β-Me2Nal). Whereas H-c[Cys-Phe-Phe-DNal-Lys-Thr-Phe-Cys]-OH (ODN-8, 2) has high affinity and marginal selectivity for human sst3 (Reubi et al., Proc. Natl. Acad. Sci. U.S.A. 2000, 97, 13973-13978), H-c[Cys-Phe-Tyr-D-threo-β -Me2Nal-Lys-Thr-Phe-Cys]-OH (5) has high affinity for all sst's except for sst1; H-c[Cys-Phe-Tyr-L-threo-β-Me2Nal-Lys-Thr-Phe-Cys]-OH (6) has high affinity for sst4 (IC50 = 2.1 nM), with more than 50-fold selectivity toward the other receptors. Analogues 7 and 8, containing D- and L-erythro-β-Me2Nal instead of the corresponding threo derivatives at position 8, are essentially inactive at all receptors. Substitution of Tyr7 in 5 and 6 by Aph7 resulted in 9 and 10 with similar affinity patterns overall yet lowered affinity. The substitution of DCys3 for Cys3 in 5 and 6 yielded H-c[DCys-Phe-Tyr-D-threo-β-Me2Nal-Lys-Thr-Phe-Cys]-OH (11) and H-c[DCys-Phe-Tyr-L-threo-β-Me2Nal-Lys-Thr-Phe-Cys]-OH (12), with biological profiles almost identical to those of their parents 5 and 6 (i.e., high affinity for sst2-5 for 11 and high affinity and selectivity for sst4 for 12). Analogue 12, with high sst4 affinity combined with the highest sst4 selectivity among all tested compounds, is an agonist in the cAMP accumulation assay (EC50 = 1.29 nM). Cold monoiodination of 12 yielded 14, with loss of sst4 selectivity and loss of high affinity (IC50 = 21 nM). Introduction of Tyr2 in 9 and 10 and substitution of Cys3 by DCys 3, to yield 15 and 16 (IC50 = 9.8 and 61 nM, respectively, for sst4 and limited selectivity), failed to generate a high-affinity 125iodinatable sst4-selective ligand. Substitution of Phe by Tyr at position 11 in H-c[DCys-Phe-Phe-L-threo-β -Me2Nal-Lys-Thr-Phe-Cys]-OH yielded 18 (IC50 = 11.8 nM at sst 4), with limited sst4 selectivity (30-fold or greater at the other receptors) yet only slightly improved affinity over that of 14. Cold monoiodination of 18 yielded 20 (IC50 = 30 nM at sst4 and high selectivity). Whereas we were able, in this study, to identify a new family of sst4-selective, high-affinity compounds, our additional goal, to identify highly potent and sst4-selective ligands amenable to 125iodination, could not be achieved satisfactorily. On the other hand, some of the diastereomers identified in this study, such as 5, 11, 17, and 19, are very potent ligands at all receptors but sst1.
Method for synthesizing alkyne through catalytic asymmetric cross coupling (by machine translation)
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Paragraph 0205-0212; 0279-0281, (2020/01/12)
The invention belongs to the field of, asymmetric synthesis, and discloses a method for catalyzing asymmetric cross- coupling to synthesize: an alkyne, and the L method comprises, the following steps, of A: preparing B a cuprous, salt and C a: ligand; preparing a catalyst; adding a base; reacting the compound with the compound with the compound; and reacting the compound with the compound. Of these, one of them, X is selected from the group consisting of, R halogens. 1 Optionally substituted heteroarylsulfonylcyanamide groups selected from the, group consisting, of optionally substituted, phenyl groups In-flight vehicle, R6 Trialkyl silyl groups or alkyl radicals, R2 Cycloalkyl radicals optionally substituted with an, optionally substituted alkyl, (CH radical2 )n R4 Multi,layer chain, n＝0-10,R saw blade4 A group selected, from, the group consisting of phenyl, alkenyl, aralkynyls, noonyloxy,and, noonylsulfonylsulfonylsulfonylsulfonylsulfonylsulfonylsulfonylsulfonylsulfonylsulphonylsulphonylsulphonylsulphonylsulphonylsulphonylsulphonylsulphonylsulphonylsulphonylphenyl disiloxy-radicals. R3 A ligand, selected from hydrogen or any of the functional groups, is selected from the group consisting of, hydrogen and any L other functional group. The method, R disclosed by the, A invention has the, advantages of good catalytic, R ’ effect, wide application range. and high catalytic efficiency, and the, method disclosed by the, invention has the. advantages of good catalytic effect, wide application range and high catalytic efficiency. (by machine translation)
Hydrodebromination of allylic and benzylic bromides with water catalyzed by a rhodium porphyrin complex
Yang, Wu,Chen, Chen,Chan, Kin Shing
supporting information, p. 12879 - 12883 (2018/10/02)
Hydrodebromination of allylic and benzylic bromides was successfully achieved by a rhodium porphyrin complex catalyst using water as the hydrogen source without a sacrificial reductant. Mechanistic investigations suggest that bromine atom abstraction via a rhodium porphyrin metalloradical operates to give the rhodium porphyrin alkyl species and the subsequent hydrolysis of the rhodium porphyrin alkyl species to a hydrocarbon product is a key step to harness the hydrogen from water.
Visible-light-mediated benzylic sp3 C-H bond functionalization to C-Br or C-N bond
Hou, Tianyuan,Lu, Ping,Li, Pixu
supporting information, p. 2273 - 2276 (2016/05/10)
A visible-light-promoted functionalization of unactivated benzylic sp3 C-H bonds was developed. Ethylbenzene derivatives were converted to the corresponding benzyl bromides or afforded benzylamine derivatives in a one-pot manner under visible light photoredox conditions.
Synthesis of benzyl bromides with hexabromoacetone: An alternative path to drug intermediates
Joseph, Kara M.,Larraza-Sanchez, Isabel
experimental part, p. 13 - 16 (2011/02/25)
A series of benzyl bromides were efficiently prepared from the corresponding alcohols with Br3CCOCBr3/PPh3 at low temperatures and under neutral conditions. The present protocol was applied to the heterocyclic analogues and to the successful synthesis of the precursor of the antiulcer drug omeprazole, thus furnishing an alternate, mild method for the preparation of these drug intermediates. A significant steric factor was observed throughout both series supporting a SN2 mechanism.
Thioacids and thioacid salts for determining the enantiomeric excess of chiral compounds containing an electrophilic carbon center
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Page/Page column 18-19, (2010/07/02)
The invention provides novel chiral compounds including 2-methoxy-2-trifluoromethylphenylacetic thioacid useful to react with and analyze other chiral compounds that have an electrophilic chiral carbon center.
Salts of Mosher's thioacid: agents for determining the enantiomer excess of SN2 substrates
Richman, Jack E.
supporting information; experimental part, p. 2793 - 2796 (2010/07/06)
The racemic and the (S)-enantiomer of Mosher's thioacid, 2-methoxy-2-trifluoromethylphenylacetic thioacid, form air-stable salts with Proton Sponge [1,8-bis(dimethylamino)naphthalene]. These salts are powerful nucleophiles that react cleanly (SN2 inversion) in CDCl3 with optically active alkyl halides ranging in reactivities from unactivated alkyl bromides and iodides to benzylic bromides. The diastereomeric excess (de) of the thioester products indicates the enantiomeric excess (ee) of the starting alkyl halides.
TREATMENT OR PROPHYLAXIS OF PROLIFERATIVE CONDITIONS
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Page/Page column 56, (2010/11/17)
The invention relates to novel compounds for use in the treatment or prophylaxis of cancers and other proliferative conditions that are for example characterized by cells that express cytochrome P450 1B1 (CYP1B1) and allelic variants thereof. The invention also provides pharmaceutical compositions comprising one or more such compounds for use in medical therapy, for example in the treatment of prophylaxis of cancers or other proliferative conditions, as well as methods for treating cancers or other conditions in human or non-human animal patients. The invention also provides methods for identifying novel compounds for use in the treatment of prophylaxis of cancers and other proliferative conditions that are for example characterized by cells that express CYP1 B1 and allelic variants thereof. The invention also provides a method for determining the efficacy of a compound of the invention in treating cancer.
Steps toward the synthesis of a geodesic C60H12 end cap for a C3v carbon [6,6]nanotube
Hill, Thomas J.,Hughes, Richard K.,Scott, Lawrence T.
experimental part, p. 11360 - 11369 (2009/04/06)
Several shape-persistent carbon-rich nanomolecules with diameters exceeding 1.7 nm have been prepared by the aldol trimerization of 20-carbon aromatic ketones bearing chlorine atoms at various sites. These C60H27Cl3 and C
Enantiodiscrimination of racemic electrophiles by diketopiperazine enolates: asymmetric synthesis of methyl 2-amino-3-aryl-butanoates and 3-methyl-aspartates
Bull, Steven D.,Davies, Stephen G.,Epstein, Simon W.,Garner, A. Christopher,Mujtaba, Nadeam,Roberts, Paul M.,Savory, Edward D.,Smith, Andrew D.,Tamayo, Juan A.,Watkin, David J.
, p. 7911 - 7925 (2007/10/03)
Enolates of (S)-N,N′-bis-(p-methoxybenzyl)-3-iso-propylpiperazine-2,5-dione exhibit high levels of enantiodiscrimination in alkylations with (RS)-1-aryl-1-bromoethanes and (RS)-2-bromoesters, affording substituted diketopiperazines containing two new stereogenic centres in high de. Deprotection and hydrolysis of the resultant substituted diketopiperazines provides a route to the asymmetric synthesis of homochiral methyl 2-amino-3-aryl-butanoates and 3-methyl-aspartates in high de and ee.
