126378-43-6Relevant articles and documents
DIHYDROPYRIDONE AMIDES AS P2X7 MODULATORS
-
Page/Page column 23, (2010/07/04)
Compounds of the formula I: or pharmaceutically acceptable salts thereof, wherein m, n, R1, R2, R3, R4 and R5 are as defined herein. Also disclosed are methods of making the compounds and using the compounds for treatment of diseases associated with the P2X7 purinergic receptor.
Diastereomeric reissert compounds of isoquinoline and 6,7-dimethoxy-3,4- dihydroisoquinoline in stereoselective synthesis
Gibson, Harry W.,Berg, Michael A. G.,Dickson, Jennifer Clifton,Lecavalier, Pierre R.,Wang, Hong,Merola, Joseph S.
, p. 5759 - 5770 (2008/02/11)
(Chemical Equation Presented) Chiral acid chlorides were reacted with isoquinoline and 6,7-dimethoxy-3,4-dihydroisoquinoline to form diastereomeric Reissert compounds 8-11 and 18-21, respectively. The best diastereoselectivity (80:20) was achieved in formation of the 9-phenylmenthyl derivative 20. The diastereomers of 2-l-menthoxy-carbonyl-1,2-dihydroisoquinaldonitriles (S)-8/(R)-8), formed in equal amounts, were inseparable. However, the individual diastereomers of 2-cholesteryloxycarbonyl-1,2-dihydroisoquinaldonitriles ((R)-11 and (5)-11) and the 2-l-menthoxycarbonyl-6,7-dimethoxy-1,2,3,4- tetrahydroisoquinaldonitriles ((S)-19/(R)-19)) were each readily purified. (S)-8/(R)-8 (1:1) via the corresponding anions (NaH, -40°C, DMF) with pivaldehyde yielded in 82:18 predominance the S-diastereomer of 1-isoquinolyl tert-butyl carbinyl l-menthyl carbonate ((S)-12), which was obtained in pure form by a single recrystallization; hydrolysis produced 99% pure S-(-)-1-isoquinolyl tert-butyl carbinol [(S)-16]. Reactions of the anions of diastereomeric Reissert compounds, either as mixtures or pure single species, with aromatic aldehydes and alkyl halides proceeded with at best modest selectivity (diastereomeric ratios up to 66:34 and 72:28, respectively). Therefore, it is concluded that the Reissert anions are either planar or rapidly inverting tetrahedral structures.
Total synthesis of (-)-epibatidine using an asymmetric Diels-Alder reaction with a chiral n-acylnitroso dienophile
Aoyagi, Sakae,Tanaka, Ryuta,Naruse, Masaichi,Kibayashi, Chihiro
, p. 8397 - 8406 (2007/10/03)
An asymmetric total synthesis of (-)-epibatidine (1), isolated from the skin of the Ecuadorian poison frog, Epipedobates tricolor, of the family Dendrobatidae, has been achieved by virtue of the development of asymmetric hereto Diels-Alder (D-A) cycloaddition with an N-acylnitroso dienophile bearing the optically active 8-arylmenthol as a chiral source. Thus, in situ oxidation of the hydroxamic acid ent-12f incorporating the (1S,2R,5S)-8-(2- naphthyl)menthyl auxiliary was performed using the Swern conditions to produce the acylnitroso dienophile, which reacted at once with 2-chloro-5- (1,5-cyclohexadienyl)pyridine (7) to provide the (1S,4R)-meta-aza cycloadduct 24 as a major diastereoisomer. The observed facial diastereoselectivity is consistent with a transition-state model with the naphthyl group in 'stacked' position and with the acylnitroso group in the s-cis conformation, wherein π attractive interaction between the naphthyl and nitrosocarbonyl groups may contribute to facial control. Compound 24 underwent hydrogenation followed by removal of the chiral auxiliary with LiH2NBH3 and reductive cleavage of the N-O bond with Mo(CO)6 to give the amino alcohol derivative 29, which was converted to (-)-epibatidine via bromination followed by cyclization.