2215-97-6Relevant academic research and scientific papers
The cooperative effect of Lewis pairs in the Friedel-Crafts hydroxyalkylation reaction: A simple and effective route for the synthesis of (±)-carbinoxamine
Harikrishnan, Adhikesavan,Sanjeevi, Jayakumar,Ramanathan, Chinnasamy Ramaraj
, p. 3633 - 3647 (2015/03/30)
An efficient C-C bond formation strategy between aromatic/heteroaromatic π-nucleophiles and Lewis acid activated aldehydes is described. This aromatic electrophilic substitution reaction of arenes or heteroarenes is facilitated by Lewis acid AlBr3. Aromatic rings with electron donating substituents are excellent nucleophilic counterparts in this reaction, generating carbinols in excellent yields (61-94%). The formation of triarylmethanes is also witnessed in the case of certain reactive aldehydes and aromatic π-nucleophiles through reactive carbocation formation. The formation of triarylmethane is reduced to a greater extent via retardation of the second π-nucleophile addition through a Lewis base, for example, pyridine, coordination with an aluminium alkoxide intermediate. Various aliphatic aldehydes also underwent Friedel-Crafts type hydroxyalkylation and generated the expected carbinols in moderate yields (41-53%) in the presence of AlBr3. This protocol has been successfully applied to the synthesize of the (±)-carbinoxamine, a therapeutically important histamine H1 antagonist, in a one-pot manner.
B(C6F5)3: an efficient catalyst for reductive alkylation of alkoxy benzenes and for synthesis of triarylmethanes using aldehydes
Chandrasekhar,Khatun, Sanjida,Rajesh,Raji Reddy
experimental part, p. 6693 - 6697 (2010/01/18)
Tris(pentafluorophenyl)borane [B(C6F5)3] has been used as an efficient catalyst for reductive alkylation of alkoxy benzenes using aldehydes as an alkylating agent in the presence of polymethylhydrosiloxane (PMHS). Various alkylated trimethoxybenzene derivatives have been prepared in good to high yields. In addition, B(C6F5)3 was also used as a catalyst for the reaction of electron-rich arenes with aldehydes to obtain triarylmethanes. The use of reductive alkylation protocol for the synthesis of an isochroman and tetrahydroisoquinoline derivatives has also been demonstrated.
Subtle side-chain modifications of the hop phytoestrogen 8-prenylnaringenin result in distinct agonist/antagonist activity profiles for estrogen receptors α and β
Roelens, Frederik,Heldring, Nina,Dhooge, Willem,Bengtsson, Martin,Comhaire, Frank,Gustafsson, Jan-?ke,Treuter, Eckardt,De Keukeleire, Denis
, p. 7357 - 7365 (2007/10/03)
In search of therapeutic agents for estrogen-related pathologies, phytoestrogens are being extensively explored. In contrast to naringenin, 8-prenylnaringenin is a potent hop-derived estrogenic compound, highlighting the importance of the prenyl group for hormonal activity. We investigated the effects of substituting the prenyl group at C(8) with alkyl chains of varying lengths and branching patterns on estrogen receptor (ER) subtype ERα- and ERβ-binding affinities and transcriptional activities. In addition, features of the ligand-induced receptor conformations were explored using a set of specific ER-binding peptides. The new 8-alkylnaringenins were found to span an activity spectrum ranging from full agonism to partial agonism to antagonism. Most strikingly, 8-(2,2-dimethylpropyl)naringenin exhibited full agonist character on ERα, but pronounced antagonist character on ERβ. Knowledge on how ER-subtype-selective activities can be designed provides valuable information for future drug or tool compound discovery.
Antibacterial agents
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, (2008/06/13)
PCT No. PCT/US97/22356 Sec. 371 Date Mar. 29, 1999 Sec. 102(e) Date Mar. 29, 1999 PCT Filed Dec. 5, 1997 PCT Pub. No. WO98/25932 PCT Pub. Date Jun. 18, 1998Described are antibacterial agents of formula (I): X is O, S or N-R8; R1, R2, R3 and R8 are independently H, straight or branched alkyl of 1-6 carbons, cycloalkyl of 3-6 carbons, alkenyl or alkynyl of from 2 to 6 atoms, R heterocyclic ring of from 5-8 atoms with 1-3 heteroatoms as nitrogen, oxygen or sulfur, or phenyl, all of which rings may be optionally substituted up to 3 times by halogen, OR, NR2, NR'COR', CN, CO2R' or CONR2', halogen, CN, CO2R, COR, CON(R)2, CON(R'')2, SR, SON, SCO2R or SCON(R)2; R4 is H, straight or branched alkyl of from 1-6 carbon atoms, alkenyl or alkynyl of from 2 to 6 atoms, heterocyclic ring of from 5-8 atoms with 1-3 heteroatoms as nitrogen, oxygen or sulfur or phenyl, all of which rings may be optionally substituted up to 3 times by halogen, OR, NR2, NR'COR', CN, CO2R' or CONR2', halogen, CN, NO2, N(R)2, NRCOR, NRCOR'', COR, CO2R, CON(R)2, CON(R'')2, NRCON(R)2, NRCO2R; R5 is 1-6 straight or branched alkyl, a cycloalkyl of 3-6 carbons, alkenyl or alkynyl of from 2 to 6 atoms, heterocyclic ring of from 5-8 atoms with 1-3 heteroatoms as nitrogen, oxygen or sulfur or phenyl, all of which rings may be optionally substituted up to 3 times by halogen, OR, NR2, NR'COR', CN, CO2R' or CONR2', halogen, OR, N(R)2, NRCOR, NRCOR'', COR, CON(R)2, CON(R'')2, SR or SO2R; R6, R7 are independently H, straight or branched alkyl of 1-6 carbons, cycloalkyl of 3-6 carbons, COR, COR'', SO2NR2, CONR2 and these may be optionally substituted by any of the groups listed for R5; R is H, straight or branched alkyl of 1-6 carbon atoms, cycloalkyl of from 3-6 carbon atoms, heterocyclic ring of from 5-8 atoms with 1-3 heteroatoms as nitrogen, oxygen or sulfur, or pheny, all of which may be optionally substituted by halogen, OR', NR'2, NR'COR', CN, CO2R', CONR'2, R' is H, alkyl of from 1-3 carbon atoms or Ph; R'' is part of a naturally occurring amino acid connected via an amide or acyl bond as determined by the formula; halogen is any one of fluoro, chloro, bromo or iodo; or a pharmaceutically acceptable salt.
