Article
Chemistry, Organic
Yuhua Ge, Hang Wang, Hua-Nan Wang, Shu-Sheng Yu, Rui Yang, Xingyue Chen, Qin Zhao, Gang Chen
Summary: Biomimetic total syntheses of Festuclavine and Pyroclavine were achieved through a sequential radical coupling. Key steps involved intramolecular decarboxylative Giese reaction for the central C ring formation and 4-nitrobenzenesulfonyl (Ns)-directed indole C4-H olefination for the indole C4 component introduction. Additionally, D-ring formation was completed via decarboxylative alkenylation and intramolecular S(N)2 reaction.
Article
Chemistry, Organic
Eunjoon Park, Cheolwoo Bae, Cheon-Gyu Cho, Cheol-Hong Cheon
Summary: The total syntheses of the antirhine alkaloids were achieved through a series of reactions, including the cyanide-catalyzed imino-Stetter reaction and subsequent C-ring formation to generate the key intermediate. The trans-selective installation of the homoallylic alcohol side-chain at C-15 allowed the successful total syntheses of antirhine and its known epimer.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Organic
Giovanni Bernardi Rosso, Bruno Matos Paz, Ronaldo Aloise Pilli
Summary: The proposed structure for the putative Stemona alkaloid named parvistemoamide has been questioned. The study also reports on the intramolecular Friedel-Crafts alkylation of a furan molecule, leading to the synthesis of related compounds.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Organic
Wesley J. Olivier, Alex C. Bissember, Jason A. Smith
Summary: The total syntheses of Stemona alkaloids sessilifoliamides B and D, as well as the second synthesis of sessilifoliamide C, were successfully completed from a simple pyrrole substrate. The bicyclic lactam core was prepared on a gram scale via a Bronsted acid mediated cyclization and controlled oxidation with Dess-Martin periodinane. Yield percentages for the synthesis of sessilifoliamides B, C, and D were 24%, 13%, and 17% respectively, over multiple steps.
Article
Chemistry, Multidisciplinary
Feifei He, Shangbiao Feng, Yulong Zhao, Hongliang Shi, Xiaoguang Duan, Huilin Li, Xingang Xie, Xuegong She
Summary: A gold-catalyzed reaction is developed to access tricyclic cores using the commonly shared bicyclic decahydroquinoline motif. These cores are then used for the divergent total syntheses of five Lycopodium alkaloids in a concise manner. Key transformations include ring cyclization, hydration, fragmentation, and construction of specific motifs.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Hongchang Tian, Yinxia Wu, Xiujuan Li, Zhen Hao, Wenyan He, Xiangdi Huang, Wen Chen, Hongbin Zhang
Summary: In this article, we present the first total synthesis of Kopsaporine related alkaloids. Our structure-unit-based strategy utilizes intramolecular Pummerer rearrangement induced nucleophilic cyclization/aza-Prins cyclization to construct the hexahydrocarbazole skeleton, olefin migration vinylogous alkylation to establish the C20 all-carbon quaternary center, iridium complex mediated radical addition to fuse the aspidofractine framework, unprecedented IBX oxidation to introduce the alpha-hydroxyketone moiety, and bioinspired retro-Aldol/Aldol reaction to convert kopsaporine to kopsiloscine A.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Organic
Yoshihiro Ataka, Mariko Kitajima, Hayato Ishikawa
Summary: The enantioselective total synthesis of (-)-silicine and (-)-20-episilicine, which contain a chiral piperidine with three contiguous chiral centers (D-ring) and a strained seven-membered ring (C-ring) attached to an indole, has been achieved. The key steps of these syntheses include a chiral secondary amine-catalyzed formal aza-[3 + 3] cycloaddition reaction and Lewis acid-mediated irreversible ring-closing reaction.
Article
Chemistry, Organic
Peng-Zhen Sheng, Lu-Lu Li, Hongbin Zhang, Kun Wei, Yu-Rong Yang
Summary: A recently developed Ir/Cu dual catalysed allylation, which efficiently constructs vicinal tertiary and N-substituted quaternary stereogenic centres in one step with excellent enantio- and diastereoselectivity, is strategically utilised for the first time in the synthesis of two alkaloids, cephalotaxine and amathaspiramide F.
ORGANIC CHEMISTRY FRONTIERS
(2023)
Article
Chemistry, Organic
Takahiro Suzuki, Soichiro Watanabe, Wataru Ikeda, Susumu Kobayashi, Keiji Tanino
Summary: Chloropupukeananin family of compounds are complex bioactive natural products with unique skeletons. The biosynthesis involves a Diels-Alder reaction triggered by specific compounds, although the enzymes responsible have not been identified. A biomimetic synthesis of chloropupukeananin and chloropupukeanolide D has been successfully achieved, indicating a potential role of Diels-Alderases in the biosynthesis of this compound family.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Organic
Xinpei Cai, Lei Li, Ye-Cheng Wang, Jianhan Zhou, Mingji Dai
Summary: In this paper, we describe the complete synthesis of phleghenrines A and C from commercially available starting materials in 7 and 8 steps, respectively. Key steps include an inverse electron-demand Diels-Alder reaction between a masked o-benzoquinone and a N-protected enamine to generate a bicyclo[2.2.2]octenone core, a Bu''chner-Curtius-Schlotterbeck one-carbon insertion to expand the bicyclo[2.2.2]octenone to a bicyclo[3.2.2]nonenone, and Trauner's modified 2-pyridone synthesis to install the 2-pyridone moiety.
Article
Chemistry, Organic
Kuei-Wei Chiu, Yu-Hsun Tseng, Ying-Xin Li, Rong-Jie Chein
Summary: In this study, a novel biomimetic synthesis of clavicipitic acid diastereomers was reported, utilizing a DDQ-mediated crossdehydrogenative coupling (CDC) reaction. The synthesis involved Suzuki coupling for prenylation and an intramolecular CDC reaction for the construction of the azepinoindole core. The trans isomer was obtained as the major product, and the two diastereomers were separable. The CDC reaction conditions were investigated, and a plausible mechanism for diastereoselectivity was proposed.
Article
Chemistry, Multidisciplinary
Wenqiang Zhou, Tao Zhou, Mengxing Tian, Yan Jiang, Jiaojiao Yang, Shuai Lei, Qi Wang, Chongzhou Zhang, Hanyue Qiu, Ling He, Zhen Wang, Jun Deng, Min Zhang
Summary: Through the development of a new method and key reactions, the concise, collective, and asymmetric total syntheses of four schizozygane alkaloids, including the first asymmetric synthesis, have been achieved in only 11-12 steps from tryptamines.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Review
Biochemistry & Molecular Biology
Bichu Cheng, Lili Song, Fener Chen
Summary: Huperzine alkaloids, particularly Huperzine A, have shown potent inhibitory activity against acetylcholine esterase. The synthesis of Huperzine A has led to significant progress in the field and has also contributed to the total synthesis of other Huperzine alkaloids. This review focuses on the synthetic organic chemistry of Huperzines, as well as briefly covering their biosynthesis and medicinal chemistry.
NATURAL PRODUCT REPORTS
(2023)
Article
Chemistry, Organic
Vera P. Demertzidou, Maria Kourgiantaki, Alexandros L. Zografos
Summary: This study describes the development of a divergent scaffold for accessing diverse natural sesquiterpenoids. The method allows scalable synthesis of various sesquiterpenoid carbocyclic cores and reports formal syntheses of several compounds.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2021)
Article
Chemistry, Organic
Masahiro Okuyama, Nariyoshi Umekubo, Kenta Akimoto, Takahisa Shimizu, Kazuhiro Kubokoya, Nagayasu Nakajima, Yoshitake Nishiyama, Satoshi Yokoshima
Summary: Total syntheses of fawcettimine-class Lycopodium alkaloids with an imino bridge between C5 and C13 were successfully achieved. Fawcettimine was synthesized for the first time in 10 steps from a known compound, and the characteristic structures, including the imino bridge, were constructed through the formation of a bridgehead imine.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2023)
