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  • Site-selective and Metal-free Aliphatic C-H Oxidation Enabled Synthesis of [5,24,25-D3]-(25S)-Δ7-Dafachronic acid

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    Liu, W.; Li, X.; Chen, J.; Li, T.; Dong, M.; Lei, X.*
    Chem. Eur. J. 2015, 21, 5345-5349

    Abstract: Steroid hormones play significant roles in both worms and mammalians. (25S)-Δ7-Dafachronic acid (Δ7-DA, 1) is a member of dafachronic acid hormonal series which regulates both development and lifespan of C. elegans. Despite its importance, effective tools for the illumination of its mode of action are lacking. Herein, we report an efficient synthesis of trideuterated […]

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  • Ainsliadimer A selectively inhibits IKKα/β by covalently binding a conserved cysteine

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    Dong, T.; Li, C.; Wang, X.; Dian, L.; Zhang, X.; Chen, X.; Li, L.; Cao, R.; Huang, N.; He, S. *; Lei, X.*
    Nature Commun. 2015, 6, 6522

    Aberrant activation of NF-kB is associated with the development of cancer and autoimmune and inflammatory diseases. IKKs are well recognized as key regulators in the NF-kB pathway and therefore represent attractive targets for intervention with small molecule inhibitors. Herein, we report that a complex natural product ainsliadimer A is a potent inhibitor of the NF-kB […]

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  • Total Syntheses of Menisporphine and Daurioxoisoporphine C Enabled by Photoredox-Catalyzed Direct C–H Arylation of Isoquinoline with Aryldiazonium Salt

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    Jing Zhang, Jie Chen, Xiaoyun Zhang, and Xiaoguang Lei*
    J. Org. Chem. 2014, 79, 10682-10688

    Abstract Isoquinoline alkaloids are attractive natural products due to their diverse chemical structures as well as remarkable bioactivities. Herein, we report the concise total syntheses of two isoquinoline alkaloids menisporphine and daurioxoisoporphine C through a mild and efficient photoredox-catalyzed direct C–H arylation of isoquinoline core with aryldiazonium salt. This new strategy is complementary to the […]

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  • Total Syntheses of (-)-Huperzine Q, (+)-Lycopladines B and C

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    Benke Hong, Houhua Li, Jinbao Wu, Jing Zhang, and Xiaoguang Lei*
    Angew. Chem. Int. Ed. 2015, 54, 1011-1015

    Utilizing a late-stage enamine bromofunctionlization strategy, we have accomplished a 12-step total synthesis of (-)-huperzine Q as well as the first total syntheses of (+)-lycopladines B and C. We also report an unprecedented X-ray crystal structure of an unusual epoxyamine intermediate and demonstrate its useful synthetic application in natural product synthesis.

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  • Absolute Quantification of a Steroid Hormone that Regulates Development in Caenorhabditis elegans

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    Tie-Mei Li, Jie Chen, Xiangke Li, Xiao-Jun Ding, Yao Wu , Li-Feng Zhao, She Chen, Xiaoguang Lei *,Meng-Qiu Dong *
    Anal. Chem. , 2013 , 85 ,9281

    Under favorable conditions, Caenorhabditis elegans larvae grow into reproductive adults after a series of molting cycles. When environmental conditions are harsh, they arrest as dauer larvae. Dafachronic acid (DA), a C. elegans steroid hormone, is required for reproductive development. Here, we report a mass spectrometry (MS) method for absolute quantitation of DA in C. elegans. […]

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  • Necrosulfonamide inhibits necroptosis by selectively targeting the mixed lineage kinase domain-like protein

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    Daohong Liao, Liming Sun, Weilong Liu, Sudan He, Xiaodong Wang and Xiaoguang Lei*
    Med. Chem. Commun., 2014,5, 333-337

    Abstract: Through high-throughput screening of 200000 compounds and subsequent structure–activity relationship (SAR) studies we identified necrosulfonamide (NSA) as a potent small molecule inhibitor for necroptosis, induced by a combination of TNF-a, Smac mimetic, and z-VAD-fmk (T/S/Z). Applying a forward chemical genetic approach, we utilized an NSA based chemical probe to further reveal that NSA selectively […]

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  • Strategies towards the Biomimetic Syntheses of Oligomeric Sesquiterpenoids

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    Chao Li and Xiaoguang Lei*
    J. Org. Chem. 2014, 79, 3289-3295

    Congratulations on?Chao’s latest JOCSynopsis paper! Abstract: Oligomeric sesquiterpenoids, biogenetically assembled from two or three monomeric sesquiterpenoid units via diverse pathways, represent a unique class of natural products. The synthetic studies inspired by their biogenesis have offered significant impetus for the efficient construction of these architecturally complex frameworks. Here we provide an overview for the biomimetic […]

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  • Enantioselective Biomimetic Total Syntheses of Kuwanons I and J and Brosimones A and B

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    Jianguang Han, Xia Li, Yong Guan, Wenjun Zhao, William D. Wulff * and Xiaoguang Lei*
    Angew. Chem. Int. Ed. 2014, 53, 9257-9261

    The first enantioselective total syntheses of prenylflavonoid Diels-Alder natural products (-)-kuwanon I, (+)-kuwanon J, (-)-brosimone A and (-)-brosimone B have been accomplished based on a concise synthetic strategy. Key elements of the synthesis include a biosynthesis-inspired asymmetric Diels-Alder cycloaddition mediated by a chiral VANOL-boron Lewis acid, as well as a process involving regioselective Schenck ene […]

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  • Diversity-oriented synthesis of Lycopodium alkaloids inspired by the hidden functional group pairing pattern

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    Jing Zhang, Jinbao Wu, Benke Hong, Wenying Ai, Xiaoming Wang, Houhua Li & Xiaoguang Lei*
    Nat. Commun. 2014, 5, 4614

    Natural products continue to provide a rich source of inspiration for both chemists and biologists. The efficient synthesis of bioactive natural products or natural product-like molecules has offered tremendous opportunities for complex biological processes exploration and drug discovery. However, because natural products usually contain numerous stereogenic centres and polycyclic ring systems, significant synthetic challenges remain. […]

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  •  Probing the Anti-cancer Mechanism of (-)-Ainsliatrimer A through Diverted Total Synthesis and Bioorthogonal Ligation

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    Chao Li, Ting Dong, Qiang Li, and Xiaoguang Lei*
    Angew. Chem. Int. Ed. 2014, 53, 12111-12115

    Herein, we report an efficient approach for exploring the novel anti-cancer mechanism of (-)-ainsliatrimer A, a structurally complex and unique trimeric sesquiterpenoid, through a combined strategy of diverted total synthesis (DTS) and bioorthogonal ligation (TQ-ligation), which allowed us to visualize the subcellular localization of this natural product in live cells. Further biochemical studies facilitated by […]

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