- Direct Catalytic Desaturation of Lactams Enabled by Soft Enolization
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A direct catalytic method is described for the α,β-desaturation of N-protected lactams to their conjugated unsaturated counterparts under mildly acidic conditions. The reaction is consistently operated at room temperature and tolerates a wide range of functional groups, showing reactivity complementary to that of prior desaturation methods. Lactams with various ring sizes and substituents at different positions all reacted smoothly. The synthetic utility of this method is demonstrated in a concise synthesis of Rolipram. In addition, linear amides also prove to be competent substrates, and the phthaloyl-protected product serves as a convenient precursor to access various conjugated carboxylic acid derivatives. Strong bases are avoided in this desaturation approach, and the key is to merge soft enolization with a Pd-catalyzed oxidation process.
- Chen, Ming,Dong, Guangbin
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supporting information
p. 7757 - 7760
(2017/06/21)
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- THIOPHENE DERIVATIVE
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The present invention provides a compound represented by the formula (I) or its salt, solvate, or physiologically functional derivative; and a pharmaceutical composition which is useful for treatment or prevention of conditions or disorders having sensitivity to selective androgen receptor modulation, the composition comprising the above-described compound; among others:
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Page/Page column 29
(2012/03/26)
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- Pushing radical cyclization from regioselective to regiospecific: Cyclization of amidyl radicals controlled by vinylic halogen substitution
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Efficient and regiospecific 6-exo, 7-endo, 7-exo, and even 8-endo amidyl radical cyclizations can be accomplished by the direct reactions of unsaturated N-H amides if they bear a vinylic halogen (Cl, Br, I) substituent. This remarkable halogen-substitution effect could be rationalized in terms of lone pair-lone pair electron repulsion between the N radical and the vinylic halogen atom, in addition to the well-known steric and radical-stabilizing effect.
- Hu, Tianshun,Shen, Meihua,Chen, Qian,Li, Chaozhong
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p. 2647 - 2650
(2007/10/03)
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- NOVEL QUINOXALINE DERIVATIVES
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A quinoxalinone derivative of the formula (I): or a pharmaceutically acceptable salt or ester thereof, wherein; ???X is NH, S or the like; ???Y is O or the like; ???the partial structure is, for example, the formula: ???B1, B2, ....., Bn-1 and Bn, (in which n is 4 , 5 or 6) are each independently CH, N or the like; ???B'1, B'2, ....., B'n-1 and B'n (in which n is 4, 5 or 6) are each independently hydrogen or the like; and ???R is hydrogen, lower alkyl or the like.
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Page/Page column 196-197
(2008/06/13)
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- Liquid phase oxidation of saturated nitrogen-containing heterocyclics over modified MCM-41 molecular sieves
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For the first time, the liquid phase oxidation reactions of saturated N-heterocyclics like piperidine and pyrrolidine to piperidone and pyrrolidone have been carried out over modified MCM-41 molecular sieves with 30-55% yield and >80% selectivity.
- Chandrakala,Murthy,Kulkarni,Raghavan
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- Amidino derivatives useful as nitric oxide synthase inhibitors
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The current invention discloses useful pharmaceutical compositions containing amidino derivative useful as nitric oxide synthase inhibitors.
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- Amidino dervatives useful as nitric oxide synthase inhibitors
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The current invention discloses useful pharmaceutical compositions containing azepine derivatives useful as nitric oxide synthase inhibitors.
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