118-08-1Relevant articles and documents
A simple, high-yielding method for the methylenation of catechols
Zelle,McClellan
, p. 2461 - 2464 (1991)
The methylenation of a variety of catechols is described, employing cesium carbonate and bromochloromethane in dimethylformamide at 110°C or acetonitrile at reflux. The corresponding methylenedioxy derivatives are obtained in 86-97 yield. Utilization of this method provided β-hydrastine in 70% yield from its corresponding dihydroxy analog.
Studies on asymmetric total synthesis of (?)-β-hydrastineviaa chiral epoxide ring-opening cascade cyclization strategy
Cheng, Maosheng,Li, Jihui,Liu, Yongxiang,Meng, Jiaxin,Qin, Qiaohua,Song, Xinjing,Wu, Tianxiao,Zhao, Dongmei,Zheng, Yang
, p. 18953 - 18958 (2020/06/08)
Herein, facile and enantioselective approaches to synthesize the core phthalide tetrahydroisoquinoline scaffold of (?)-β-hydrastineviaboth a CF3COOH-catalyzed (86% ee) and KHMDS-catalyzed (78% ee) epoxide ring-opening/transesterification cascade cyclization from chiral epoxide under very mild conditions are described. The key elements include a highly enantioselective epoxidation using the Shi ketone catalyst and an intramolecular CF3COOH-catalyzed cascade cyclization in one pot, and a late-stage C-3′ epimerization under MeOK/MeOH conditions as the key steps to achieve the first total synthesis of (?)-β-hydrastine (up to 81% ee).
Novel composition for treatment of decubitus ulcers
-
, (2008/06/13)
A composition for treatment of decubitus ulcers comprising an admixture of from about 10 to about 50 parts lecithin, from about 10 to about 50 parts goldenseal root or rhizome, and from about 10 to about 50 parts myrrh gum.
Novel Zinc-Promoted Alkylation of Iminium Salts. New Synthesis of Benzylisoquinoline, Phthalidylisoquinoline, and Protoberberine Alkaloids and Related Compounds
Shono, Tatsuya,Hamaguchi, Hiroshi,Sasaki, Manji,Fujita, Shumei,Nagami, Kimihiko
, p. 1621 - 1628 (2007/10/02)
Zinc-promoted reductive coupling reaction of iminium salts with alkyl halides was found to be a successful key reaction for synthesis of a variety of alkaloids such as benzylisoquinoline, phthalidylisoquinoline, and protoberberine alkaloids.More specifically, laudanosine, cordrastine, hydrastine, narcotine, tetrahydropalmatine, and canadine were obtained.A new route for the synthesis of the emetine and yohimbine skeletons was exploited.
Some Reactions of β-Hydrastine
Chatterjee, A.,Bhattacharyya, S.,Bhattacharyya, S.
, p. 74 - 76 (2007/10/02)
β-Hydrastine (I) is an erythro compound, the chiral centres at C-1 and C-9 having R and S configurations respectively.Its conversion into the hitherto unknown threo-isomer by the reduction of the corresponding immonium derivative (II) with zinc and acetic acid has met with failure.Surprisingly, II with Zn/ AcOH regenerates β-hydrastine.During this reduction II rather suffers reductive cleavage yielding the non-nitrogenous lactone, meconine (IV).Sodium borohydride and catalytic reductions of II also fail to afford the threo-isomer.The latter is found to be extremely unstable as revealed from Dreiding model because of the severe steric interaction between the axial hydrogen at C-4 and the C1'-C2'bond.Benzylic oxidation of β-hydrastine (I) with MnO2, instead of producing the desired 4-oxo derivative (VI), gives 6,7-methylenedioxyisoquinoline arising out of cleavage at C1-C9 bond.
NEW ELECTROREDUCTIVE SYNTHESIS OF PHTHALIDE ALKALOIDS
Shono, Tatsuya,Usui, Yoshihiro,Hamaguchi, Hiroshi
, p. 1351 - 1354 (2007/10/02)
Electroreduction of 2-methyl-3,4-dihydro-6,7-dimethoxy-isoquinolinium salt in the presence of 3-bromomeconine afforded Cordrastine.The method of cross coupling of immonium salts with bromophthalides was also applicable to other phthalide alkaloids.
THE ALKALOIDS OF Hydrastis canadensis L. (RANUNCULACEAE). TWO NEW ALKALOIDS: HYDRASTIDINE AND ISOHYDRASTIDINE
Messana, Irene,La Bua, Roberto,Galeffi, Corrado
, p. 539 - 544 (2007/10/02)
Ten alkaloids have been isolated from rhizomes and roots of Hydrastis canadensis L.Four of them, viz. berberine, 1, β-hydrastine, 2, canadine, 3, and canadaline, 4, had been previously isolated.Two are new phthalideisoquinoline alkaloids, viz. 3'-O-demethyl-β-hydrastine, named hydrastidine, 5, and 4'-O-demethyl-β-hydrastine, named isohydrastidine, 6.Two are (-)-(S)-corypalmine, 7, and (-)-(S)-isocorypalmine, 8, known mono-O-demethyl derivatives of (-)-(S)-tetrahydropalmatine, 9.One, 10, is a bis-O,O'-demethyl derivative of 9, whose hydroxy groups were not located, whereas the structure of the tenth alkaloid is still unknown. 1H NMR data for 1-8 and 10, and 13C NMR data for 5, 6, and 8 are reported.
