6882-28-6Relevant academic research and scientific papers
Enantioselective synthesis of 1-aryl tetrahydroisoquinolines by the rhodium-catalyzed reaction of 3,4-dihydroisoquinolinium tetraarylborates
Li, Wei-Sian,Kuo, Ting-Shen,Wu, Ping-Yu,Chen, Chien-Tien,Wu, Hsyueh-Liang
supporting information, p. 1141 - 1146 (2021/02/16)
The 1-aryl tetrahydroisoquinolines (1-aryl THIQs) are omnipresent in biologically active molecules. Here we report on the direct asymmetric synthesis of these valuable compounds via the reaction of 3,4-dihydroisoquinolinium tetraarylborates. The dual roles of anionic tetraarylborates, which function as both prenucleophiles and stabilizers of 3,4-dihydroisoquinolinium cations, enable this rhodium(I)-catalyzed protocol to convergently provide enantioenriched 1-aryl THIQs in good yields (≤95%) with ≤97% ee, as demonstrated by the formal synthesis of (?)-solifenacin and the facile synthesis of (?)-Cryptostyline I.
Structural optimization of berberine as a synergist to restore antifungal activity of fluconazole against drug-resistant Candida albicans
Liu, Hong,Wang, Liang,Li, Yan,Liu, Jiang,An, Maomao,Zhu, Shaolong,Cao, Yongbing,Jiang, Zhihui,Zhao, Mingzhu,Cai, Zhan,Dai, Li,Ni, Tingjunhong,Liu, Wei,Chen, Simin,Wei, Changqing,Zang, Chengxu,Tian, Shujuan,Yang, Jingyu,Wu, Chunfu,Zhang, Dazhi,Liu, Hua,Jiang, Yuanying
supporting information, p. 207 - 216 (2014/01/17)
We have conducted systematic structural modification, deconstruction, and reconstruction of the berberine core with the aim of lowering its cytotoxicity, investigating its pharmacophore, and ultimately, seeking novel synergistic agents to restore the effectiveness of fluconazole against fluconazole-resistant Candida albicans. A structure-activity relationship study of 95 analogues led us to identify the novel scaffold of N-(2-(benzo[d][1,3]dioxol-5-yl)ethyl)-2- (substituted phenyl)acetamides 7 a-l, which exhibited remarkable levels of in vitro synergistic antifungal activity. Compound 7 d (N-(2-(benzo[d][1,3]dioxol- 5-yl)ethyl)-2-(2-fluorophenyl)acetamide) significantly decreased the MIC 80 values of fluconazole from 128.0 μg mL-1 to 0.5 μg mL-1 against fluconazole-resistant C. albicans and exhibited much lower levels of cytotoxicity than berberine toward human umbilical vein endothelial cells. Build it better: Structural optimization of berberine led to the identification of the novel scaffold of N-(2-(benzo[d][1,3]dioxol-5-yl) ethyl)-2-(substituted phenyl)acetamides 7 a-l, which exhibited remarkable in vitro synergistic antifungal activity against fluconazole-resistant Candida albicans in combination with fluconazole. Compound 7 d exhibited much lower cytotoxicity than berberine toward human umbilical vein endothelial cells. Copyright
Short synthesis of noscapine, bicuculline, egenine, capnoidine, and corytensine alkaloids through the addition of 1-siloxy-isobenzofurans to imines
Soriano, Maria Del Pilar C.,Shankaraiah, Nagula,Santos, Leonardo Silva
scheme or table, p. 1770 - 1773 (2010/05/18)
A concise diastereotioselective strategy for the synthesis of noscapine, bicuculline, and egenine (1a-c), as well as capnoidine and corytensine (2a,b), was developed using diastereoselective addition of 1-siloxy-isobenzofurans 4a and 4b to iminium ion 5 in a one-pot approach. The synthesis features the use of imine 13 obtained through Bischler-Napieralsky reaction from amine 11. The addition of ionic liquids as addictives in the reactions afforded erythro configuration in major adduct compounds. The synthetic route can also be applied in the total synthesis of promising tubulin binding agent EM105 (3).
Activation of iodosobenzene by catalytic tetrabutylammonium iodide and its application in the oxidation of some isoquinoline alkaloids
Huang, Wei-Jan,Singh, Om V.,Chen, Chung-Hsiung,Chiou, Sheng-You,Lee, Shoei-Sheng
, p. 1069 - 1078 (2007/10/03)
Oxidation of N-methyltetrahydroisoquinolines with iodosylbenzene in the presence of a catalytic amount of tetrabutylammonium iodide in various solvents afforded N-methyl-2H-3,4-dihydroisoquinol-1-ones in almost quantitative yields. The application of this finding to the oxidation of other isoquinolines, including tetrahydroisoquinolines, lycorine diacetate, and benzyltetrahydroisoquinolines, also afforded the corresponding lactams in good yields, however, accompanied by a few minor byproducts. Under similar conditions, tetrahydroberberine gave a rearranged compound, berberal, as the major product, accompanied by 8-oxoberberine and berberine.
Aza analogues of protoberberine and phtalideisoquinoline alkaloids
Jahangir,MacLean, David B.,Holland, Herbert L.
, p. 1031 - 1035 (2007/10/02)
Anions derived from furopyridin-3(1H)-one, by treatment with lithium diisopropylamide, react with substituted, 3,4-dihydroisoquinolines and 2-methyl-3,4-dihydroisoquinolinium salts yielding nitrogen analogues of protoberberine and phtalideisoquinoline alkaloids, respectively.
Ruthenium-catalysed Oxidation of Secondary Amines to Imines using t-Butyl Hydroperoxide
Murahashi, Shun-Ichi,Naota, Takeshi,Taki, Hiroshi
, p. 613 - 614 (2007/10/02)
The ruthenium-catalysed oxidation of secondary amines with t-butyl hydroperoxide under mild conditions affords the corresponding imines in high yields.
Condensation of cyclic and acyclic imines with phthalide anions. Synthesis of protoberberines and substituted 3,4-dihydro-2-methyl-1(2H)-isoquinolones
Marsden, Richard,MacLean, David B.
, p. 1392 - 1399 (2007/10/02)
3,4-Dihydroisoquinolines react with anions derived from phthalides and 3-methylphthalides in tetrahydrofuran yielding 13-hydroxy-8-oxotetrahydroprotoberberines and 13-hydroxy-13-methyl-8-oxotetrahydroprotoberberines, respectively.Only one of two possible diastereomers is formed.The lactams may be reduced to the corresponding protoberberines with lithium aluminium hydride.The reaction of the acyclic imine, 3,4-dimethoxybenzylidenemethylamine, with anions derived from phthalide, 3-phenylphthalide, and 5,6-dimethoxyphthalide, has been investigated.In all cases separable mixtures of diastereomeric substituted 3,4-dihydro-1(2H)-isoquinolones were formed.
Synthesis and Antihypertensive Activity of a Series of Spiroquinolizine-2,5'-oxazolidin-2'-one>s
Caroon, Joan M.,Clark, Robin D.,Kluge, Arthur F.,Lee, Chi-Ho,Strosberg, Arthur M.
, p. 1426 - 1433 (2007/10/02)
The 2R*,11bS* and 2S*,11bS* diastereoisomers of the spiroquinolizine-2,5'-oxazolidin-2'-one> system were prepared by stereoselective methods.Evaluation of these compounds for antihypertensive activity by oral administration to the spontaneously hypertensive rat showed the 2S*,11bS* series was the more potent.Within that series it was found that small alkyl substituents at positions 3 and 4' enhanced antihypertensive activity and that methoxyl substitution at positions 9 and 10 was optical. (2S,3S,11bS)-Spiroquinolizine-2,5'-oxazolidin-2'-one> was one of the most efficacious compounds of this series, while its antipode, (+)-9e, was inactive.Selected compounds in this series were shown to be α-adrenoceptor antagonists.
Synthesis of phthalideisoquinolines from 3-halophthalides and 3,4-dihydroisoquinolinium salts
Slemon, Clarke E.,Hellwig, Louise C.,Ruder, Jean-Pierre,Hoskins, Eric W.,MacLean, David B.
, p. 3055 - 3060 (2007/10/02)
Phthalideisoquinoline alkaloids have been synthesized by coupling appropriately substituted 3-halophthalides and 2-methyl-3,4-dihydroisoquinolinium salts in the presence of Zn(Cu) couple or metallic Zn.Both erythro and threo isomers are formed in the reaction.The nmr spectra of the (+/-)-erythro- and (+/-)-threo-isocordrastines have been reinvestigated.The results, which differ from those previously reported, lead to a different conclusion regarding the conformations of the molecules.
