- Unexpected formation of 3,3a,4,7a-tetrahydrobenzofuran-2,5-dione as well as arene carboxylic acids upon formal double exo nucleophilic addition of R1R2C-COO- to anisolechromium tricarbonyl complexes
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Bis(trimethylsily)ketene acetals of the general structure 2 (R1 = H,Me,R2 = Me,Et,Pr(i),CMe = CH2) react at -78°C in the presence of Bu(t)OK with a series of arenechromium tricarbonyl complexes 3 to give as expected, after oxidation with I2 followed by silica gel chromatography, arylcarboxylic acids 7. In the case of anisolechromium tricarbonyl 8, besides the m-methoxyarylcarboxylic acids, tetrahydrobenzofuran-2,5-diones 11, are formed as the result of a double nucleophilic addition.
- Bellassoued, Moncef,Chelain, Evelyne,Collot, Jerome,Rudler, Henri,Vaissermann, Jacqueline
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Read Online
- Palladium-Catalyzed Distal m-C-H Functionalization of Arylacetic Acid Derivatives
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Herein, we present m-C-H olefination on derivatives of phenylacetic acids by tethering with a simple nitrile-based template through palladium catalysis. Notably, the versatility of the method is evaluated with a wide range of phenylacetic acid derivatives for obtaining the meta-olefination products in fair to excellent yields with outstanding selectivities under mild conditions. Significantly, the present strategy is successfully exemplified for the synthesis of drugs/natural product analogues (naproxen, ibuprofen, paracetamol, and cholesterol).
- Srinivas, Dasari,Satyanarayana, Gedu
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supporting information
p. 7353 - 7358
(2021/10/01)
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- Cobalt-catalyzed C[sbnd]H activation/C[sbnd]O formation: Synthesis of benzofuranones
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Herein, C[sbnd]H activation/C[sbnd]O formation reaction using novel cobalt catalytic system is reported. This reaction was given benzofuranones in moderate to excellent yields at room-temperature under air reaction conditions. The introduced strategy is efficient and low-cost method to synthesized benzofuranones from α,α-disubstitution acetic acid.
- Hajipour, Abdol R.,Khorsandi, Zahra
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- Palladium(II)-Catalyzed C(sp2)-H Carbonylation of Sterically Hindered Amines with Carbon Monoxide
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A palladium-catalyzed, amine-directed C(sp2)-H carbonylation of α,α-disubstituted benzylamine under 1 atm of CO for the facile synthesis of sterically hindered benzolactam has been developed. The key to success is the use of 2,2,6,6-tetramethyl-1-piperidinyloxy as the crucial sole oxidant. The synthetic utility of this transformation has been demonstrated by the first concise synthesis of the natural product spiropachysin-20-one.
- Cheng, Xiu-Fen,Wang, Tao,Li, Yan,Wu, Yun,Sheng, Jie,Wang, Rui,Li, Chao,Bian, Kang-Jie,Wang, Xi-Sheng
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supporting information
p. 6530 - 6533
(2018/10/20)
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- Novel, potent and selective 17β-hydroxysteroid dehydrogenase type 2 inhibitors as potential therapeutics for osteoporosis with dual human and mouse activities
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17β-Hydroxysteroid dehydrogenase type 2 (17β-HSD2) is responsible for the oxidation of the highly active estradiol (E2) and testosterone (T) into the less potent estrone (E1) and Δ4-androstene-3,17-dione (Δ4-AD), respectively. As 17β-HSD2 is present in bones and as estradiol and testosterone are able to induce bone formation and repress bone resorption, inhibition of this enzyme could be a new promising approach for the treatment of osteoporosis. Herein, we describe the design, the synthesis and the biological evaluation of 24 new 17β-HSD2 inhibitors in the 5-substituted thiophene-2-carboxamide class. Structure-activity and structure-selectivity relationships have been explored by variation of the sulfur atom position in the central core, exchange of the thiophene by a thiazole, substitution of the amide group with a larger moiety, exchange of the N-methylamide group with bioisosteres like N-methylsulfonamide, N-methylthioamide and ketone, and substitutions at positions 2 and 3 of the thiophene core with alkyl and phenyl groups leading to 2,3,5-trisubstituted thiophene derivatives. The compounds were evaluated on human and mouse enzymes. From this study, a novel highly potent and selective compound in both human and mouse 17β-HSD2 enzymes was identified, compound 21 (IC 50(h17β-HSD2) = 235 nM, selectivity factor toward h17β-HSD1 = 95, IC50 (m17β-HSD2) = 54 nM). This new compound 21 could be used for an in vivo proof of principle to demonstrate the true therapeutic efficacy of 17β-HSD2 inhibitors in osteoporosis. New structural insights into the active sites of the human and mouse enzymes were gained.
- Perspicace, Enrico,Cozzoli, Liliana,Gargano, Emanuele M.,Hanke, Nina,Carotti, Angelo,Hartmann, Rolf W.,Marchais-Oberwinkler, Sandrine
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p. 317 - 337
(2014/07/21)
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- NEW COMPOUNDS
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The present invention encompasses compounds of general formula (1) wherein A, B, X, R1 to R3 are defined as in claim 1, which are suitable for the treatment of diseases characterised by excessive or abnormal cell proliferation, and t
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Page/Page column 32
(2010/07/10)
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- CYCLIC DIARYL ETHER COMPOUNDS AS ANTAGONISTS OF PROSTAGLANDIN D2 RECEPTORS
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Described herein are compounds that are antagonists of PGD2 receptors. Also described are pharmaceutical compositions and medicaments that include the antagonists of PGD2 receptors described herein, as well as methods of using such antagonists of PGD2 receptors, alone and in combination with other compounds, for treating respiratory, cardiovascular, and other PGD2-dependent or PGD2-mediated conditions or diseases.
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Page/Page column 110
(2009/10/09)
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- (3-HYDROXY-4-AMINO-BUTAN-2-YL) -3- (2-THIAZOL-2-YL-PYRROLIDINE-1-CARBONYL) BENZAMIDE DERIVATIVES AND RELATED COMPOUNDS AS BETA-SECRETASE INHIBITORS FOR TREATING
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The present invention provides novel beta-secretase inhibitors and methods for their use, including methods of treating of Alzheimer's disease. (Formula)
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Page/Page column 119
(2009/05/29)
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- HYDROXYETHYLAMINE DERIVATIVES FOR THE TREATMENT OF ALZHEIMER'S DISEASE
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The present invention relates to novel hydroxyethylamine compounds of formula (I): (I) having Asp2 (-secretase, BACE1 or Memapsin) inhibitory activity, processes for their preparation, to compositions containing them and to their use in the treatment of diseases characterised by elevated-amyloid levels or-amyloid deposits, particularly Alzheimer's disease.
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- TRICYCLIC INDOLE DERIVATIVES AND THEIR USE IN THE TREATMENT OF ALZHEIMER’S DISEASE
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The present invention relates to novel hydroxyethylamine compounds having Asp2 (β-secretase, BACE1 or Memapsin) inhibitory activity, processes for their preparation, to compositions containing them and to their use in the treatment of diseases characterised by elevated β- amyloid levels or β-amyloid deposits, particularly Alzheimer's disease.
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- Heteroarotinoids inhibit head and neck cancer cell lines in vitro and in vivo through both RAR and RXR retinoic acid receptors
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A class of less toxic retinoids, called heteroarotinoids, was evaluated for their molecular mechanism of growth inhibition of two head and neck squamous cell carcinoma (HNSCC) cell lines SCC-2 and SCC-38. A series of 14 heteroarotinoids were screened for growth inhibition activity in vitro. The two most active compounds, one that contained an oxygen heteroatom (6) and the other a sulfur heteroatom (16), were evaluated in a xenograph model of tumor establishment in nude mice. Five days after subcutaneous injection of 107 SCC-38 cells, groups of 5 nu/nu mice were gavaged daily (5 days/week for 4 weeks) with 20 mg/kg/day of all-trans-retinoic acid (t-RA, 1), 10 mg/kg/day of 6, 10 mg/kg/day of 16, or sesame oil. After a few days, the dose of t-RA (1) was decreased to 10 mg/kg/day to alleviate the side effects of eczema and bone fracture. No significant toxic effects were observed in the heteroarotinoid groups. All three retinoids caused a statistically significant reduction in tumor size as determined by the student t-test (P 0.05). Complete tumor regression was noted in 3 of 5 mice treated with t-RA (1), 4 of 5 mice treated with 16, 1 of 5 mice treated with 6, and 1 of 5 mice treated with sesame oil. Reverse transcriptase polymerase chain reaction (RT- PCR) was used to determine that the expression levels of RARα, RXRα, and RXRβ were similar in the two cell lines, while RARβ expression was higher in SCC-2 over SCC-38, and RARγ expression was higher in SCC-38 over SCC-2. Receptor cotransfection assays in CV-1 cells demonstrated that 16 was a potent activator of both RAR and RXR receptors, while 6 was selective for the RXR receptors. Transient cotransfection assays in CV-1 cells using an AP-1 responsive reporter plasmid demonstrated that t-RA (1), 6, and 16 each inhibited AP-1-driven transcription in this cell line. In conclusion, the growth inhibition activity of the RXR-selective 6 and the more potent growth inhibition activity of the RAR/pan-agonist 16 implicate both RARs and RXRs in the molecular mechanism of retinoid growth inhibition. Moreover, the chemoprevention activity and the lack of toxicity of heteroarotinoids demonstrate their clinical potential in head and neck cancer chemoprevention.
- Zacheis, David,Dhar, Arindam,Lu, Shennan,Madler, Matora M.,Klucik, Jozef,Brown, Chad W.,Liu, Shengquan,Clement, Francis,Subramanian, Shankar,Mahika Weerasekare,Darrell Berlin,Gold, Michael A.,Houck Jr., John R.,Fountain, Kenneth R.,Benbrook, Doris M.
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p. 4434 - 4445
(2007/10/03)
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- Cyclic nitrones
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The present invention is directed to novel cyclic nitrones and their use in the prevention of oxidation tissue damage by free radicals, their use in the treatment of a number of disease states in which radicals either damage or destroy tissues via oxidation, and pharmaceutical compositions containing these cyclic nitrones.
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- Design, synthesis, and in vitro evaluation of cyclic nitrones as free radical traps for the treatment of stroke
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Analogs of the cyclic nitrone free radical trap 1 (3,3-dimethyl-3,4- dihydroisoquinoline N-oxide, a cyclic analog of phenyl-tert-butylnitrone (PBN)) were prepared in which (1) the fused phenyl ring was replaced with a naphthalene ring, an electron rich heterocycle, or a dimethylphenol, (2) the nitrone-containing ring comprised five, six, or seven atoms, and (3) the gem- dimethyl group was replaced with spirocyclic groups. The most active antioxidant, which bears a dimethylphenol fused to a 7-membered ring nitrone (compound 6h), inhibited lipid peroxidation in vitro with an IC50 of 22 μM, a 75-fold improvement over that of 1. The previously observed correlation between lipophilicity and activity vs lipid peroxidation in vitro has been further substantiated and refined by this study. Moreover, certain classes of compounds (namely, dimethylphenols 6g, h and furan 6j) have now been found which are considerably more active in vitro than expected on the basis of their log k'(w) values.
- Fevig, Thomas L.,Bowen, S. Marc,Janowick, David A.,Jones, Bryan K.,Munson, H. Randall,Ohlweiler, David F.,Thomas, Craig E.
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p. 4988 - 4996
(2007/10/03)
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- SYNTHESIS OF 7,7-DIMETHYLAPORPHINE ALKALOIDS
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The synthesis of N,O,O-trimethyltetrahydromelosmine (1,2,3,9-tetramethoxy-7,7-dimethylaporphine) (3) is described.The amide deriative (9), prepared from the appropriate acid (8) and amine (6) by condensation, was cyclized by a Bischler-Napieralski reactio
- Ammar, Hassan A.,Schiff, Paul L.,Slatkin, David J.
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p. 451 - 454
(2007/10/02)
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