The Experts below are selected from a list of 264 Experts worldwide ranked by ideXlab platform
Jieping Zhu - One of the best experts on this subject based on the ideXlab platform.
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IBX‐Mediated Oxidative Ugi‐Type Multicomponent Reactions: Application to the N and C1 Functionalization of Tetrahydroisoquinoline
Angewandte Chemie (International ed. in English), 2007Co-Authors: Tifelle Ngouansavanh, Jieping ZhuAbstract:An Ugi-type reaction of Tetrahydroisoquinoline with an isocyanide and a carboxylic acid in the presence of iodoxybenzoic acid (IBX) afforded the 1,2-diacylated adduct in good to excellent yields. E.g., in the presence of IBX, reaction of 1,2,3,4-Tetrahydroisoquinoline, PhCO2H, and BnNC gave 87% 2-benzoyl-N-benzyl-1,2,3,4-Tetrahydroisoquinoline-1-carboxamide (I). [on SciFinder (R)]
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ibx mediated oxidative ugi type multicomponent reactions application to the n and c1 functionalization of Tetrahydroisoquinoline
Angewandte Chemie, 2007Co-Authors: Tifelle Ngouansavanh, Jieping ZhuAbstract:An Ugi-type reaction of Tetrahydroisoquinoline with an isocyanide and a carboxylic acid in the presence of iodoxybenzoic acid (IBX) afforded the 1,2-diacylated adduct in good to excellent yields. E.g., in the presence of IBX, reaction of 1,2,3,4-Tetrahydroisoquinoline, PhCO2H, and BnNC gave 87% 2-benzoyl-N-benzyl-1,2,3,4-Tetrahydroisoquinoline-1-carboxamide (I). [on SciFinder (R)]
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Diethyl oxomalonate as a three carbon synthon for synthesis of functionalized 1,1′-disubstituted Tetrahydroisoquinoline
Tetrahedron Letters, 2001Co-Authors: Michèle Bois-choussy, Sebastien Cadet, Michaël De Paolis, Jieping ZhuAbstract:Pictet–Spengler condensation of β-arylethylamine with diethyl oxomalonate provides an entry to highly functionalized 1,1′-disubstituted Tetrahydroisoquinoline in high yield. Selective functionalization of two ester groups is demonstrated. Syntheses and functional group transformations of 1,1-disubstituted Tetrahydroisoquinoline are reported.
Lei Liu - One of the best experts on this subject based on the ideXlab platform.
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Catalytic Enantioselective Alkynylation of Tetrahydroisoquinoline-Based N-Acyl Hemiaminals
Synthesis, 2016Co-Authors: Shutao Sun, Lei LiuAbstract:A highly enantioselective catalytic alkynylation of Tetrahydroisoquinoline-based N-acyl hemiaminals has been developed. The method is simple and exhibits a broad scope with respect to both heterocycles and terminal alkynes, thus allowing for facile construction of a variety of enantiopure α-substituted Tetrahydroisoquinolines.
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Highly Enantioselective Catalytic Cross-Dehydrogenative Coupling of N-Carbamoyl Tetrahydroisoquinolines and Terminal Alkynes.
ChemInform, 2015Co-Authors: Shutao Sun, Paul E. Floreancig, Hongxiang Lou, Lei LiuAbstract:The reaction provides access to 1-alkinyl substituted 1,2,3,4-Tetrahydroisoquinolines while tolerating a range of functional groups on both, the Tetrahydroisoquinoline and the alkyne moiety.
Yun Liang - One of the best experts on this subject based on the ideXlab platform.
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copper catalyzed c sp3 s bond and c sp2 s bond cross coupling of 2 2 iodobenzoyl substituted or 2 2 iodobenzyl substituted 1 2 3 4 Tetrahydroisoquinolines with potassium sulfide synthesis of isoquinoline fused 1 3 benzothiazine scaffolds
Journal of Organic Chemistry, 2017Co-Authors: Pan Dang, Zhilei Zheng, Yun LiangAbstract:The sulfuration reaction of 2-(2-iodobenzoyl) substituted, or 2-(2-iodobenzyl) substituted 1,2,3,4-Tetrahydroisoquinolines with potassium sulfide proceeded in the presence of copper catalysts to give Tetrahydroisoquinoline-fused 1,3-benzothiazine scaffolds in moderate to appropriate yields. This protocol provided an efficient and simple strategy to construct the corresponding benzothiazine derivatives via formation of C(sp3)-S bond and C(sp2)-S bond, which the C-S bonds formed via different routes in this reaction (traditional cross-coupling reaction via the cleavage of C-I bond and oxidative cross-coupling reaction via C(sp3)-H bond functionalization).
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Copper-Catalyzed C(sp3)–S Bond and C(sp2)–S Bond Cross-Coupling of 2‑(2-Iodobenzoyl) Substituted or 2‑(2-Iodobenzyl) Substituted 1,2,3,4-Tetrahydroisoquinolines with Potassium Sulfide: Synthesis of Isoquinoline-Fused 1,3-Benzothiazine Scaffolds
2017Co-Authors: Pan Dang, Zhilei Zheng, Yun LiangAbstract:The sulfuration reaction of 2-(2-iodobenzoyl) substituted, or 2-(2-iodobenzyl) substituted 1,2,3,4-Tetrahydroisoquinolines with potassium sulfide proceeded in the presence of copper catalysts to give Tetrahydroisoquinoline-fused 1,3-benzothiazine scaffolds in moderate to appropriate yields. This protocol provided an efficient and simple strategy to construct the corresponding benzothiazine derivatives via formation of C(sp3)–S bond and C(sp2)–S bond, which the C–S bonds formed via different routes in this reaction (traditional cross-coupling reaction via the cleavage of C–I bond and oxidative cross-coupling reaction via C(sp3)–H bond functionalization)
Shutao Sun - One of the best experts on this subject based on the ideXlab platform.
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Catalytic Enantioselective Alkynylation of Tetrahydroisoquinoline-Based N-Acyl Hemiaminals
Synthesis, 2016Co-Authors: Shutao Sun, Lei LiuAbstract:A highly enantioselective catalytic alkynylation of Tetrahydroisoquinoline-based N-acyl hemiaminals has been developed. The method is simple and exhibits a broad scope with respect to both heterocycles and terminal alkynes, thus allowing for facile construction of a variety of enantiopure α-substituted Tetrahydroisoquinolines.
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Highly Enantioselective Catalytic Cross-Dehydrogenative Coupling of N-Carbamoyl Tetrahydroisoquinolines and Terminal Alkynes.
ChemInform, 2015Co-Authors: Shutao Sun, Paul E. Floreancig, Hongxiang Lou, Lei LiuAbstract:The reaction provides access to 1-alkinyl substituted 1,2,3,4-Tetrahydroisoquinolines while tolerating a range of functional groups on both, the Tetrahydroisoquinoline and the alkyne moiety.
Lucyna Antkiewicz-michaluk - One of the best experts on this subject based on the ideXlab platform.
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A possible physiological role for cerebral Tetrahydroisoquinolines.
Neurotoxicity Research, 2003Co-Authors: Jerzy Vetulani, Lucyna Antkiewicz-michaluk, Irena Nalepa, M. SansoneAbstract:Tetrahydroisoquinolines present in the mammalian brain, 1,2,3,4-Tetrahydroisoquinoline (TIQ) and salsolinol, suspected to cause neurodegeneration leading to Parkinson's disease, were investigated to find their possible physiological role. To this aim their behavioral and receptor effects induced after a single dose were tested in mice and rats. Both compounds do not affect significantly the basal locomotor activity, very effectively block hyperactivity induced by apomorphine (rats) and amphetamine (mice), only partially block hyperactivity induced by scopolamine, do not affect locomotor stimulation induced by cocaine, and strongly augment the running fit induced by morphine (mice). They do not produce extrapyramidal symptoms and do not potentiate haloperidol-induced catalepsy (rats). TIQ and salsolinol do not displace antagonists of several receptors (including D1 and D2) from their binding sites, but displace the agonists of α2-adrenoreceptors, [3H] clonidine and of dopamine receptors, [3H] apomorphine. The results indicate that salsolinol and TIQ act as specific antagonists of agonistic conformation of dopamine receptors, and owing to that may play a role of endogenous feed-back regulators of the dopaminergic system. Those properties make Tetrahydroisoquinolines potential antidopaminergic drugs devoid of extrapyramidal effects, with possible application in substance addiction disorder as anti-craving agents.
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A possible physiological role for cerebral Tetrahydroisoquinolines.
Neurotoxicity research, 2003Co-Authors: Jerzy Vetulani, Lucyna Antkiewicz-michaluk, Irena Nalepa, M. SansoneAbstract:Tetrahydroisoquinolines present in the mammalian brain, 1,2,3,4-Tetrahydroisoquinoline (TIQ) and salsolinol, suspected to cause neurodegeneration leading to Parkinson's disease, were investigated to find their possible physiological role. To this aim their behavioral and receptor effects induced after a single dose were tested in mice and rats. Both compounds do not affect significantly the basal locomotor activity, very effectively block hyperactivity induced by apomorphine (rats) and amphetamine (mice), only partially block hyperactivity induced by scopolamine, do not affect locomotor stimulation induced by cocaine, and strongly augment the running fit induced by morphine (mice). They do not produce extrapyramidal symptoms and do not potentiate haloperidol-induced catalepsy (rats). TIQ and salsolinol do not displace antagonists of several receptors (including D(1) and D(2)) from their binding sites, but displace the agonists of Alpha(2)-adrenoceptors, [(3)H]clonidine and of dopamine receptors, [(3)H]apomorphine. The results indicate that salsolinol and TIQ act as specific antagonists of agonistic conformation of dopamine receptors, and owing to that may play a role of endogenous feed-back regulators of the dopaminergic system. Those properties make Tetrahydroisoquinolines potential antidopaminergic drugs devoid of extrapyramidal effects, with possible application in substance addiction disorder as anti-craving agents.
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Opposite effect of simple Tetrahydroisoquinolines on amphetamine- and morphine-stimulated locomotor activity in mice.
Journal of neural transmission (Vienna Austria : 1996), 2001Co-Authors: Jerzy Vetulani, Lucyna Antkiewicz-michaluk, Irena Nalepa, M. SansoneAbstract:Endogenous Tetrahydroisoquinolines, such as 1,2,3,4-Tetrahydroisoquinoline (TIQ) and 1-methyl-6,7-dihydroxy-1,2,3,4-Tetrahydroisoquinoline (salsolinol), were tested for their interaction with motor effects of amphetamine and morphine in C57BL/6 mice. TIQ binding to cortical adrenergic α1, α2 and β receptors, striatal dopamine D1 and D2 receptors and cortical L-type calcium channels in the Wistar rat was also studied. Both compounds in high doses reduced the mouse locomotor activity, and in doses not affecting activity inhibited the motor stimulation induced by amphetamine, 2 or 3 mg/kg ip, but facilitated the hyperactivity induced by 10 mg/kg of morphine. TIQ did not displace ligands that are antagonists for several receptor sites (including D1 and D2 receptors), but displaced an agonist of α2-adrenoceptor, clonidine. It is proposed that TIQ and salsolinol specifically antagonize the agonistic conformation of dopamine receptor and that endogenous 1,2,3,4-Tetrahydroisoquinolines may play a role of natural feedback regulators of the activity of dopaminergic system.
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Neurochemical changes induced by acute and chronic administration of 1,2,3,4-Tetrahydroisoquinoline and salsolinol in dopaminergic structures of rat brain.
Neuroscience, 2000Co-Authors: Lucyna Antkiewicz-michaluk, Irena Romańska, Iwona Papla, Jerzy Michaluk, M. Bakalarz, Jerzy Vetulani, Anna Krygowska-wajs, Andrzej SzczudlikAbstract:The finding that endogenous Tetrahydroisoquinolines may be involved in the etiology of Parkinson's disease suggests that their administration may cause changes resembling those observed in parkinsonian brain. We tested, using a high-performance liquid chromatography method, how single and chronic administration of 1,2, 3,4-Tetrahydroisoquinoline and salsolinol affects dopamine and serotonin metabolism in the neurons of extrapyramidal and mesolimbic dopaminergic systems. We report that chronic administration of Tetrahydroisoquinoline and salsolinol causes a decrease in a dopamine metabolism: the effect of Tetrahydroisoquinoline was limited to the striatum, while salsolinol caused also a dramatic decline of dopamine level in the substantia nigra. The effect of both compounds on serotonin metabolism was small or absent. The Tetrahydroisoquinolines produced no changes in the nucleus accumbens. The results indicate that Tetrahydroisoquinoline and salsolinol specifically affect the nigrostriatal dopamine system, but only when administered chronically, and thus are compatible with the view that endogenous Tetrahydroisoquinolines may participate in pathogenesis of Parkinson's disease.
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Antidopaminergic Effects of Putative Endogenous MPTP-Like Agents: 1,2,3,4-Tetrahydroisoquinoline and 1-Methyl-6,7-Dihydroxy-l,2,3,4-Tetrahydroisoquinoline
Neurotoxic Factors in Parkinson’s Disease and Related Disorders, 2000Co-Authors: Lucyna Antkiewicz-michaluk, Irena Romańska, Jerzy MichalukAbstract:Tetrahydroisoquinolines, such as 1,2,3,4-Tetrahydroisoquinoline (TIQ) and its derivative l-methyl-6,7-dihydroxy-l,2,3,4-Tetrahydroisoquinoline (salsolinol), aroused considerable interest as molecular species that may be implicated in etiology of Parkinson’s disease (Nagatsu and Yoshida, 1988; Gerlach and Riederer, 1996; Nagatsu, 1997). The suspicions that Tetrahydroisoquinolines may be neurotoxic resulted from their ability to form isoquinolinium ions, analogous to MPP+ (Maruyama et al., 1997, Naoi et al., 1994).
