25908-92-3Relevant academic research and scientific papers
Design, synthesis and in-vitro biological evaluation of antofine and tylophorine prodrugs as hypoxia-targeted anticancer agents
Abdalla, Ashraf N.,Abdullah, Omeima,Chen, Linwei,Fischer, Peter M.,Guise, Chris P.,Liu, Yuxiu,Omran, Ziad,Patterson, Adam V.,Rauch, Cyril,Sindi, Ikhlas A.,Smaill, Jeff B.,Wang, Qingmin
, (2021/06/21)
Phenanthroindolizidines, such as antofine and tylophorine, are a family of natural alkaloids isolated from different species of Asclepiadaceas. They are characterized by interesting biological activities, such as pronounced cytotoxicity against different human cancerous cell lines, including multidrug-resistant examples. Nonetheless, these derivatives are associated with severe neurotoxicity and loss of in vivo activity due to the highly lipophilic nature of the alkaloids. Here, we describe the development of highly polar prodrugs of antofine and tylophorine as hypoxia-targeted prodrugs. The developed quaternary ammonium salts of phenanthroindolizidines showed high chemical and metabolic stability and are predicted to have no penetration through the blood–brain barrier. The designed prodrugs displayed decreased cytotoxicity when tested under normoxic conditions. However, their cytotoxic activity considerably increased when tested under hypoxic conditions.
Total synthesis of (R)-tylophorine by using an asymmetric hydrogenation of the allyl alcohol
Li, Rui,Liu, Chun-Fang,Yu, Chun-Jiao,Gu, Peiming
, p. 2170 - 2172 (2018/05/04)
An efficient synthesis of naturally occurring (R)-tylophorine is described. The alkaloid was prepared in seven steps from a known phenanthryl aldehyde with an overall yield of 14.2%. Asymmetric hydrogenation of an allyl alcohol was employed as a key step for installing a stereogenic center with good enantioselectivity (77% ee), and the ee value of the ω-chloro alcohol was improved to 95% by recrystallization. After azidation and oxidation of the enantio-enriched ω-chloro alcohol to the precursor of the Schmidt reaction, the chirality transfer in the stereospecific 1,2-migration furnished the chiral carbon in the alkaloid. Finally, a one-pot deformylation/Pictet-Spengler cyclization completed the total synthesis of (R)-tylophorine.
Two optically pure isomers of NK007 and bactericidal applications
-
, (2016/10/09)
The invention relates to two optically pure isomers of NK007 for short and applications in a bactericidal aspect. Compounds NK007-3 and NK007-4 have good bactericidal activity, can be used for treating plant bacteria diseases selected from fusarium wilt of cucumber, cercospora brown spot of peanut, apple ring spot, alternaria solani, puccinia polysora, rice bakanae disease, sclerotinia rot of colza, phytophthora capsici disease, wheat sharp eyespot, bipolaris maydis, watermelon anthracnose, potato late blight, rice sheath blight disease and cucumber gray mold.
Asymmetric Total Synthesis of Tylophorine through a Formal [2+2] Cycloaddition Followed by Migrative Ring Opening of a Cyclobutane
Yamaoka, Yousuke,Taniguchi, Marie,Yamada, Ken-Ichi,Takasu, Kiyosei
, p. 2819 - 2825 (2015/09/15)
The asymmetric total synthesis of phenanthroindolizidine alkaloid (-)-tylophorine was achieved by asymmetric transfer hydrogenation of a cyclic imine. The cyclic imine with a pendant phenanthrene core was synthesized by a TfOH-promoted domino ring-contraction/ring-opening sequence of a cyclobutanol bearing an azide group, which was constructed by a formal [2+2] cycloaddition of a 2′-vinyl-1,1′-biaryl-2-yl ketone enolate. Catalytic asymmetric hydrogenation of the cyclic imine intermediate allowed the late-stage construction of the asymmetric center.
Collective asymmetric synthesis of (-)-Antofine, (-)-cryptopleurine, (-)-tylophorine, and (-)-tylocrebrine with tert- butanesulfinamide as a chiral auxiliary
Zheng, Yanlong,Liu, Yuxiu,Wang, Qingmin
, p. 3348 - 3357 (2014/05/06)
A collective asymmetric synthesis of phenanthroindolizidine and phenanthroquinolizidine alkaloids (-)-antofine, (-)-cryptopleurine, (-)-tylophorine, and (-)-tylocrebrine was achieved by means of a reaction sequence involving efficient generation of chiral homoallylic amine intermediates by asymmetric allylation of the corresponding tert-butanesulfinyl imine. From these intermediates, the pyrrolidine and piperidine rings were constructed by means of an intramolecular SN2 substitution reaction and a ring-closing metathesis reaction, respectively. The unusual C5-methoxy-substituted phenanthrene moiety of (-)-tylocrebrine was generated by means of an InCl3-catalyzed cycloisomerization reaction of an o-propargylbiaryl compound.
Short asymmetric synthesis of phenanthroindolizidines through chiral homoallylic sulfinamines
Anton-Torrecillas, Cintia,Gonzalez-Gomez, Jose C.
, p. 7018 - 7025 (2014/10/15)
An efficient stereocontrolled preparation of chiral phenanthroindolizidines is detailed. The synthesis relies on the stereoselective indium-mediated allylation of 2-(phenanthren-9-yl)acetaldehyde derivatives with chiral tert-butylsulfinamide. Chemoselecti
An enantioselective strategy for the total synthesis of (S)-tylophorine via catalytic asymmetric allylation and a one-pot DMAP-promoted isocyanate formation/Lewis acid catalyzed cyclization sequence
Su, Bo,Zhang, Hui,Deng, Meng,Wang, Qingmin
, p. 3616 - 3621 (2014/06/09)
A new asymmetric total synthesis of a phenanthroindolizidine alkaloid (S)-tylophorine is reported, which features a catalytic asymmetric allylation of aldehydes and an unexpected one-pot DMAP promoted isocyanate formation and Lewis acid catalyzed intramolecular cyclization reaction. In addition, White's direct C-H oxidation catalyst system converting monosubstituted olefins to linear allylic acetates was also employed for late-stage transformation. This journal is the Partner Organisations 2014.
Concise synthesis of tylophorine
Lin, Qi-Xian,Ho, Tse-Lok
, p. 2996 - 3001 (2013/03/29)
The phenanthroindolizidine alkaloid tylophorine has been synthesized in the (R)- and racemic forms. One of the routes involves three steps from a known compound employing a Stevens rearrangement as the pivotal reaction. The phenanthrene moiety was constructed by either a base-catalyzed cyclization of 2-alkynylbiphenyls or a double Suzuki coupling of a 2,2′-dibromobiphenyl with vic-bis(pinacolatoboryl)alkene in other routes.
Synthesis of tylocrebrine and related phenanthroindolizidines by VOF 3-mediated oxidative aryl-alkene coupling
Niphakis, Micah J.,Georg, Gunda I.
supporting information; experimental part, p. 196 - 199 (2011/03/19)
A highly convergent strategy to prepare phenanthroindolizidines is reported involving three consecutive C-C coupling reactions. This sequence features a novel VOF3-mediated aryl-alkene coupling in the final step, which enables regioselective preparation of C5-substituted phenanthroindolizidines for the first time. This strategy has been applied to the synthesis of eight natural and unnatural members in this class to investigate the scope of this chemistry and to explore structure-activity relationships.
Asymmetric palladium-catalyzed carboamination reactions for the synthesis of enantiomerically enriched 2-(Arylmethyl)- and 2-(Alkenylmethyl)pyrrolidines
Mai, Duy N.,Wolfe, John P.
supporting information; experimental part, p. 12157 - 12159 (2010/11/03)
The enantioselective synthesis of 2-(arylmethyl)- and 2-(alkenylmethyl) pyrrolidine derivatives via Pd-catalyzed alkene carboamination reactions is described. These transformations generate enantiomerically enriched products with up to 94% ee from readily
