Search results for "Tetrahydroisoquinoline"

A one-pot cascade to protoberberine alkaloids via Stevens rearrangement of nitrile-stabilized ammonium ylides.

2015

A facile one-pot synthesis of protoberberines from readily accessible 1,2,3,4-tetrahydroisoquinoline-1-carbonitriles and 1,2-bis(bromomethyl)arenes is described. The reaction cascade comprises four consecutive transformations, all of which can be effected under a single set of conditions. Ten protoberberines, including the alkaloids pseudopalmatine and pseudoepiberberine, were prepared in yields up to 86% according to this strategy. No chromatographic purification of the products is required, and the route is devoid of any protecting group manipulations.

Optimization of a LC method for the enantioseparation of a non-competitive glutamate receptor antagonist, by experimental design methodology

2006

Abstract The aim of this work was to obtain the direct optical resolution of a new glutamate receptor antagonist (( p -chloro)1-aryl-6,7,-dimethoxy-1,2,3,4-tetrahydroisoquinoline, PS3), by liquid chromatography on Chiralcel ® OD column. A response surface methodology (RSM) was employed to optimize the enantiomeric separation of the racemate with the lowest number of experiments; in particular, a face-centred design (FCD) was applied to evaluate the influence of critical parameters on the experimental response. Furthermore, in order to find the best compromise between several responses, a multicriteria decision-making approach, the Derringer's desirability function, was successful to simulta…

CCDC 633704: Experimental Crystal Structure Determination

2007

Related Article: R.Gitto, R.Ficarra, R.Stancanelli, M.Guardo, L.De Luca, M.L.Barreca, B.Pagano, A.Rotondo, G.Bruno, E.Russo, G.De Sarro, A.Chimirri|2007|Bioorg.Med.Chem.|15|5417|doi:10.1016/j.bmc.2007.05.059

Syntheses of dopaminergic 1-cyclohexylmethyl-7,8-dioxygenated tetrahydroisoquinolines by selective heterogeneous tandem hydrogenation

2002

Abstract We describe the preparation in a ‘one-pot’ sequence 1-cyclohexylmethyl 7,8-dioxygenated tetrahydroisoquinoline, substituted and unsubstituted in the C ring by application of the Photo–Fries transposition, followed by a tandem reduction–cyclization and further reduction. Indeed, we have accomplished for the first time regioselective hydrogenation of the benzylic ring of the tetrahydroisoquinoline systems. All 1-cyclohexylmethyl THIQ synthesized were able to displace D2 dopamine receptor from its specific binding site in rat striatal membranes, while the N-methylated derivatives showed also affinity for D1 dopamine receptors.

A Highly Enantioselective Access to Tetrahydroisoquinoline and β-Carboline Alkaloids with Simple Noyori-Type Catalysts in Aqueous Media

2009

Synthesis and Conformational Analysis of Tetrahydroisoquinoline-Fused 1,3,2-Oxazaphospholidines and 1,2,3-Oxathiazol­idines

2008

The cyclizations of tetrahydroisoquinoline 1,2-amino alcohols with phenylphosphonic dichloride, bis(2-chloroethyl)phosphoramidic dichloride, thionyl chloride and sulfuryl chloride were utilized to synthesize 1,5,6,10b-tetrahydro-1,3,2-oxazaphospholo[4,3-a]isoquinolines (2, 3), 1,5,10,10a-tetrahydro-1,3,2-oxazaphospholo[3,4-b]isoquinolines (8, 9), 1,5,6,10b-tetrahydro-1,2,3-oxathiazolo[4,3-a]isoquinolines (4–6) anda 1,5,10,10a-tetrahydro-1,2,3-oxathiazolo[3,4-b]isoquinoline (11), which are the first representatives of these ring systems. NMR spectroscopic analysis revealed the existence of conformational equilibria that are fast on the NMR timescale. Theoretical DFT calculations pointed to t…

Structure-activity relationship of dopaminergic halogenated 1-benzyl-tetrahydroisoquinoline derivatives

2009

Two series of halogenated 1-benzyl-7-chloro-6-hydroxy-tetrahydroisoquinolines were prepared to explore the influence of each series on the affinity for dopamine receptors. All the compounds displayed a high affinity for D(1)-like and/or D(2)-like dopamine receptors in striatal membranes, although they were unable to inhibit [(3)H]-dopamine uptake in striatal synaptosomes. The halogen placed on the benzylic ring in 1-benzyl-THIQs, compounds of the series 1, 2'-bromobenzyl derivatives with K(i) values into the nanomolar range, and the series 2, 2',4'-dichlorobenzyl-THIQ homologues, proves to be an important factor to modulate affinity at dopamine receptor. (C) 2009 Elsevier Masson SAS. All ri…

New strategies for medical management of overactive bladder in children.

2011

Purpose of review The medical treatment of children with non-neurogenic overactive bladder syndrome (OAB) is still limited to a small number of drugs approved for use in childhood according to the national regulations of each country. Recent findings Over the last few years, there were several studies on the use of antimuscarinics other than oxybutynin in children, as well as some on the use of extended release oxybutynin and tolterodine and transdermal oxybutynin. It was shown that the combination of two different anticholinergics might be a well tolerated and successful option in children with OAB refractory to monotherapy, as well as administration of a receptor-selective antimuscarinic …