- Method for synthesizing benzophenanthridine and protoberberine alkaloids through modular diversity regulation and control
-
The invention discloses a method for synthesizing benzophenanthridine and protoberberine alkaloids through modular diversity regulation and control. The method comprises the following steps: improving a substituent group of a high-iodine salt leaving group, generating pyridine alkyne under the action of relatively mild potassium tert-butoxide, and carrying out [4 + 2] cycloaddition reaction on the pyridine alkyne and diene to obtain polysubstituted isoquinoline ring precursor compounds. Ring opening and aromatization of the isoquinoline ring precursor are realized by developing a novel iridium-catalyzed cross-coupling method, polysubstituted isoquinoline ring compounds with connecting capacity are efficiently synthesized, and then the polysubstituted isoquinoline ring compounds are coupled with a high-activity polysubstituted cyclic boric acid to obtain 3-aryl isoquinoline high-grade intermediates. Through application of two different chemical principles, regulation and control of the 3-aryl isoquinoline high-grade intermediates are realized, and benzophenanthridine and protoberberine alkaloids are modularly, diversely and efficiently synthesized.
- -
-
-
- A General, Concise Strategy that Enables Collective Total Syntheses of over 50 Protoberberine and Five Aporhoeadane Alkaloids within Four to Eight Steps
-
A concise, catalytic, and general strategy that allowed efficient total syntheses of 22 natural 13-methylprotoberberines within four steps for each molecule is reported. This synthesis represents the most efficient and shortest route to date, featuring three catalytic processes: CuI-catalyzed redox-A3 reaction, Pd-catalyzed reductive carbocyclization, and PtO2-catalyzed hydrogenation. Importantly, this new strategy to the tetracyclic framework has also been applied to the collective concise syntheses of >30 natural protoberberines (without 13-methyl group) and five aporhoeadane alkaloids.
- Zhou, Shiqiang,Tong, Rongbiao
-
p. 7084 - 7089
(2016/05/19)
-
- Facile synthesis of tetrahydroprotoberberine and protoberberine alkaloids from protopines and study on their antibacterial activities
-
A series of isoquinoline alkaloids including tetrahydroprotoberberines, N-methyl tetrahydroprotoberberines and protoberberines were facile synthesised with protopines as the starting material. All compounds were evaluated for their antibacterial activities against four pathogenic bacteria Escherichia coli, Staphyloccocus aureus, Staphylococcus gallinarum and Salmonella choleraesuis. Experimental results indicated that protoberberines were the most active compounds to the target bacteria among the tested alkaloids. It was suggested that planar molecule with high aromatisation level (e.g. coptisine 5 and berberine 6) or a positive charge of the molecules (e.g. N-methyl tetrahydroprotoberberines 11 and 12) had a positive influence on the antibacterial effects.
- Cheng, Pi,Wang, Bin,Liu, Xiubin,Liu, Wei,Kang, Weisong,Zhou, Jie,Zeng, Jianguo
-
supporting information
p. 413 - 419
(2014/04/17)
-
- Design, synthesis and multidrug resistance reversal activity evaluation of 8-oxocoptisine derivatives
-
Fifteen derivatives of 8-oxocoptisine were prepared based on that 8-oxocoptisine showed potent reversing effect against human cancer cells charactering multidrug resistance (MDR). The derivatives were evaluated for their growth inhibition and effects on r
- Wu, Jian Bo,Lei, Fan,Cui, Xiang Juan,He, Yun,Hai, Li,Zhang, Juan,Wu, Yong
-
experimental part
p. 742 - 748
(2012/09/08)
-
- TRANSFORMATION OF PROTOBERBERINES INTO SPIROBENZYLISOQUINOLINES. STEREOSELECTIVE CONVERSION OF COPTISINE INTO (+/-)-OCHROBIRINE
-
Reduction of the 8,14-cycloberbin-13-one (7a), derived from coptisine, (6a), with LiAlH(OBut)3 gave stereoselectively the alcohol (8a) which was subsequently treated with ethyl chloroformate to afford the oxazolidinone (10a).Hydrolysis of 10a followed by methylation with methyl iodide provided (+/-)-ochrobirine (1a).KEYWORDS - ochrobirine, spirobenzylisoquinoline alkaloid; coptisine; berberine; protoberberine alkaloid; stereoselective reduction; ethyl chloroformate; regioselectivce C8-N bond cleavage; stereoselective transformation
- Hanaoka, Miyoji,Sakurai, Shun-ichiro,Ohshima, Takeshi,Yasuda, Shingo,Mukai, Chisato
-
p. 3446 - 3449
(2007/10/02)
-
