The First Total Synthesis of Natural 6β-Cinnamoyloxy-1α- hydroxy-5, 10-bis-epi-eudesm-4-en-3-one

The first total synthesis of natural 6β-cinnamoyloxy-1α-hydroxy-5, 10-bis-epi- eudesm-4-en-3-one （1）, a highly complex natural eudesmane, was described.

固载化SnCl_4催化合成3-甲基-3-丁烯-1-醇

采用两步气相法制备了固载化SnCl_4催化剂,并将其用于异丁烯与甲醛Prins缩合合成3-甲基-3-丁烯-1-醇(MBOH)。考察了载体和溶剂种类对Prins缩合反应的影响。实验结果表明,以SiO_2为载体制备的SnCl_4/SiO_2催化剂有利于提高MBOH的收率和选择性;同时强极性的非质子性溶剂二氧六环能够促进聚甲醛的解聚,提高反应体系中甲醛的溶解度,有利于碳正离子的形成,促进Prins缩合反应的进行。在SnCl_4/SiO_2催化剂用量0.24mmol(以催化剂中SnCl_4的物质的量计)、异丁烯用量8.4g、聚甲醛用量1.5g、二氧六环用量15mL、100℃、2.2MPa条件下反应3h,MBOH的选择性为81%,MBOH的收率达到55%。当SnCl_4/SiO_2催化剂循环使用4次时,MBOH的收率降为45%,表明该催化剂具有一定的重复使用性。

催化合成3-甲基-3-丁烯-1-醇醋酸酯及其水解过程研究

采用酯化水解两步法高效合成3-甲基-3-丁烯-1-醇(MBOH)。首先采用硅烷嫁接法制备了MCM-48嫁接SnCl2催化剂,应用于多聚甲醛、异丁烯和醋酸缩合酯化制备3-甲基-3-丁烯-1-醇醋酸酯(MB-AC),然后MB-AC碱性水解制备MBOH,并对缩合酯化和水解反应进行工艺条件考察。结果表明,最佳缩合酯化反应条件为:2.4 g催化剂,16 g多聚甲醛,120 g异丁烯,128 g醋酸,反应温度140℃,反应时间6 h。在此条件下,MB-AC的收率为55.5%,MBOH的收率为13.8%。进一步将缩合酯化反应产物碱性水解,最佳水解条件为:水解温度50℃,进料速度为60 mL/h,碱溶液质量分数为20%。在此条件下,水解收率为94.5%。酯化水解两步法制备MBOH的总收率达到65.5%。

Stereoselective Synthesis of 3(R) and 3(S)-Hydroxyeicos-4(E)-en-1-yne, a Component of the Marine Sponge Cribrochalina Vasculum

Stereocontrolled synthesis of 3(R) and 3(S)-hydroxyeicos-4(E)-en-1-yne has been achieved through double elimination of chloride intermediates 8 and 11, which were prepared from acetylenic alcohol intermediates 1 and 10.

A Triterpenoid Inhibited Hormone-Induced Adipocyte Differentiation and Alleviated Dexamethasone-Induced Insulin Resistance in 3T3-L1 adipocytes

6a-Hydroxylup-20(29)-en-3-on-28-oic acid(1),a natural triterpenoid,was found to possess the ability in a dose-dependent manner inhibiting hormone-induced adipocyte differentiation in 3T3-L1 preadipocytes,and restoring glucose consuming ability in dexamethasone(DXM)-induced insulin resistant 3T3-L1 adipocytes.Compound 1 was also found to ameliorate DXM-induced adipocyte dysfunction in lipolysis and adipokine secretion.Mechanistic studies revealed that 1 inhibited adipocyte differentiation in 3T3-L1 preadipocytes via down-regulating hormone-stimulated gene transcription of peroxisome proliferator-activated receptor c and CCAAT-enhancer-binding protein alpha which are key factors in lipogenesis,and restored DXM-impaired glucose consuming ability in differentiated 3T3-L1 adipocytes via repairing insulin signaling pathway and activating down-stream signaling transduction by phosphorylation of signaling molecules PI3K/p85,Akt2 and AS160,thus leading to increased translocation of glucose transporter type 4 and transportation of glucose.

Synthesis of Gingerenone C and 5-Hydroxy-1-(4′-hydroxy-3-methoxyphenyl)-7-(4′′-hydroxyphenyl)-3-heptanone

The two diarylheptanoids (E)-1-(4-hydroxy-3-methoxyphenyl)-7-(4-hydroxyphenyl) hept-4-en-3-one 1 (Gingerenone C) and (±)-5-hydroxy-1-(4-hydroxy-3-methoxyphenyl)-7-(4- hydroxyphenyl)-3-heptanone 2 were synthesized from vanillin 3 and 4-hydroxybenzaldehyde 9.

Antiviral stereoisomers of 3,5-bis(2-hydroxybut-3-en-1-yl)-1,2,4-thiadiazole from the roots of Isatis indigotica

Four stereoisomers of 3,5-bis（2-hydroxybut-3-en-1-yl）-l,2,4-thiadiazole, named insatindigothiadia- zoles A-D （1a-1d）, were isolated from the roots oflsatis indigotica. Their structures were determined by spectroscopic analysis; specifically, the absolute configurations were assigned by using the MPA determination rule based on △δrs values of MPA esters, and supported by electronic CD （ECD） calculations. Proposed biosynthetic pathways and preliminary investigations of the biological activities of la-1d against influenza virus A （H3N2）, Coxsackie virus B3, and/or HSV-1 are also discussed.

Synthesis and Fungicidal Activity of （E）-5-[1-（2-Oxo- 1 -oxaspiro[4,5]dec/non-3-en-3-yl）ethylidene]-2- aminoimidazolin-4-one Derivatives

The novel fungicidal agents, （E）-5-[1-（2-oxo-l-oxaspiro[4,5]dec/non-3-en-3-yl）ethylidene]-2-aminoimidazolin- 4-one derivatives, were designed and synthesized in moderate to excellent yields in four steps using a-hydroxyketone and diketene as raw materials and characterized by HR-ESI-MS, 1H NMR and X-ray diffraction. The preliminary bioassay showed that some of these compounds, such as 5e, 6a, 6e, and 7h exhibit 87.8%, 91.3%, 89.9% and 87.8% inhibition rates against Sclerotinia scleotiorum, 3b, 3c, 4c and 7h exhibit 96.4%, 92.5%, 90.3% and 76.9% inhibition rates against Phytophthora capsici at the concentration of 50 μg/mL, respectively. These compounds exhibited significant fungicidal activities against S. scleotiorum and P. capsici with EC50 values of 2.56 --11.60 μg/mL, and compounds 6e and 7h exhibited weak inhibition against the spore germination of S. scleoti- orum, while the spore germination ofP. capsici was strongly inhibited by compound 7h solution. Scanning electron microscopy （SEM） and transmission electron microscopy （TEM） observation indicated that compound 7h had a significant impact on the structure and function of the hyphal cell wall ofP. capsici mycelium.

Visible-Light-Promoted Formation of C-C and C-P Bonds Derived from Evolution of Bromoalkynes under Additive-Free Conditions:Synthesis of 1,1-Dibromo-1-en-3-ynes and Alkynylphosphine Oxides

Main observation and conclusion The controllable achievement of C-C and C-P bond formations is developed via visible-light-promoted bromoalkyne dimerization or its further transformation with secondary phosphine oxides.The 1,1-dibromo-1-en-3-ynes are formed when bromoalkyne is exposed to visible-light.While alkynylphosphine oxides are generated when bromoalkynes are mixed with secondary phosphine oxides.

新型白念珠菌生物被膜抑制剂IMB-H12的活性和作用机制研究

白念珠菌是真菌感染疾病中的主要病原菌,生物被膜的形成是白念珠菌毒力特征,同时也是重要的耐药机制,开发具有生物被膜抑制活性的抗真菌药物具有重要的意义。本研究对前期获得的新型的具有生物被膜抑制活性的化合物1-(cyclopentylamino)-3-(4-(2,4,4-trimethylpentan-2-yl)phenoxy)propan-2-ol(简称IMB-H12)进行了深入的研究。IMB-H12对生物被膜的形成具有良好的抑制活性,并且对成熟的生物被膜具有一定的清除作用;初步作用机制研究发现IMB-H12能够抑制酵母-菌丝相的转换、抑制菌丝体的形成,降低白念珠菌的黏附活性和疏水性;IMB-H12能够诱导生物被膜菌细胞壁成分含量的改变,下调多个与黏附和菌丝形成相关的基因的表达。因此,对该化合物的进一步研究,有望发现新型的具有抗真菌活性的先导化合物。

吉祥草的化学成分研究

目的：对吉祥草的化学成分进行研究。方法：利用萃取，硅胶、凝胶和反相硅胶柱色谱以及高效液相色谱法进行分离和纯化，采用谱学技术（1D和2D NMR谱，MS，IR等）进行结构鉴定。结果：从吉祥草中分离鉴定了6个化合物，分别是1α，3β-dihydroxy-5β-pregn-16-en-20-one 3-O-β-D-glucopyranoside（1），syringaresinol-β-D-gluco-side（2），sophoraflavoneB（3），stigmast-5，22-dien-3-O-β-D-glucopyranoside（4），胡萝卜苷（5），α-D-glucose（6）。结论：化合物1为新化合物，化合物2～6为首次从该植物中分离得到。

红蓼果实中的一个新三萜皂苷(英文)

为了研究红蓼果实的化学成分,利用硅胶和反相柱色谱方法进行分离纯化,根据理化性质和光谱数据鉴定其化合物结构,分离并鉴定了3个化合物:28-O-β-D-glucopyranosyl-3β,7β-dihydroxy-lup-20(29)-en-28-oate(1),5,7-二羟基色原酮(2)和柚皮素(3)。化合物1为新化合物,化合物2,3为首次从该植物中分离得到。

冬虫夏草定殖菌Aspergillus fumigatus中一个新的聚酮类化合物

从冬虫夏草中分离得到一株定殖菌烟曲霉,对其发酵液的乙酸乙酯萃取部位进行化学成分研究,借助正反相硅胶柱色谱及HPLC等方法进行分离纯化,分离得到一个聚酮类新化合物1,利用多种波谱手段(HRESI-MS,1D NMR,2D NMR)确定其结构为为6-methoxy-3-methyl-1H-isochromen-8-ol。化合物1对H1299(人肺癌细胞)、H460(大细胞肺癌细胞)、HGC-27(人胃癌细胞)、A549(人非小细胞肺癌细胞)和mnk-43(人胃癌高分化细胞)五种细胞株均有弱的细胞毒活性。

Two New Pentacyclic Triterpenes from Sabia parviflora

Two new pentacyclic triterpene acids, 1a, 3b-dihydroxyl-olean-12-en-28-oic acid and 1a, 2a, 3b-trihydroxyl-olean-12-en-28-oic acid, were isolated from the arial parts of Sabia parviflora.

A new prenylated arylbenzofuran derivative from Morus alba L.

2-[3,5-Di-O-β-D-glucosyl-4-(3-methylbut-2-enyl)phenyl]benzofuran-6-ol,a new prenylated arylbenzofuran derivative was isolated from Morus alba L.Its structure was elucidated by various spectroscopic methods including MS,~1H NMR,^(13)C NMR,DEPT,~1H-~1HCOSY,HMQC and HMBC.

A new triterpene and a saponin from Centella asiatica

A new triterpene and a saponin, named 2α,3β23-trihydroxyurs-20-en-28-oic acid （1） and 2α,3β,23-trihydroxyurs-20-en-28-oic acid O-α-L-rhanmopyranosyl-（1→4）-O-β-D-glucopyranosyl-（1→6）-O-β-D-glucopyranosyl ester （2）, have been isolated from the aerial part of CenteUa asiatica. Their structures were elucidated by spectral methods, including 2D-NMR spectra.

Bioactive Compounds and Insecticidal Activity of Hysterionica pinifolia, a Native South American Plant

Phytochemical investigation of the purified fractions of the active dichloromethane extract of Hysterionica pinifolia (Poir.) Baker led to the identification of five compounds. New acetylenic alcohol (E)-undec-3-en-5,7-diyne-1-ol (1) and three other compounds (3), (4), and (5) were reported for the first time in this species. Furthermore, forty-six components from the volatile fraction of H. pinifolia were identified. These compounds were elucidated using 1D and 2D NMR spectroscopy as well as MS-ESI and GC-FID-MS experiments. The dichloromethane extract, its fractions, and the methanolic extract were tested for insecticidal activity against Tribolium castaneum under laboratory conditions. The dichloromethane extract and the fraction F2 were found to be active, showing high larval mortality. The dichloromethane extract was also active against T. castaneum adults. The results have shown that H. pinifolia could be considered, in a near future, as a potential source for the development of a botanical insecticide for pest control.

Co-Catalyzed Dehydrogenation Claisen Condensation of Secondary Alcohols with Esters

Comprehensive Summary Catalytic dehydrogenation,with its exceptional atom economy and chemoselectivity,offers a highly desirable yet challenging approach for converting multiple environmentally friendly alcohols into crucial molecules.Furthermore,the utilization of catalysts based on abundant elements found on Earth for alcohol dehydrogenation to produce acryl ketone holds significant promise as a versatile strategy in synthesizing key building blocks for numerous pharmaceutical applications.The present study describes a practical Co-catalyzed cascade dehydrogenative Claisen condensation of secondary alcohols with esters,facilitating the synthesis of a wide range of 3-hydroxy-prop-2-en-1-ones.We introduce a catalytic system based on novel and scalable indazole NNP-ligands coordinated to cobalt for efficient dehydrogenations of secondary alcohols,and propose a plausible reaction mechanism supported by control experiments and labeling studies.Notably,it allows for the streamlined synthesis of multiple pharmaceuticals in one-pot.

Identification and biosynthesis of plant papanridins,a group of novel oligomeric flavonoids

The discovery of novel flavonoids and elucidation of their biosynthesis are fundamental to understanding their roles in plants and their benefits for human and animal health.Here,we report a new pathway for polymerization of a group of novel oligomeric flavonoids in plants.We engineered red cells for discovering genes of interest involved in the flavonoid pathway and identified a gene encoding a novel flavanol polymerase(FP)localized in the central vacuole.FP catalyzes the polymerization of flavanols,such as epicatechin and catechin,to produce yellowish dimers or oligomers.Structural elucidation shows that these compounds feature a novel oligomeric flaven–flavan(FF)skeleton linked by interflavan–flaven and interflaven bonds,distinguishing them from proanthocyanidins and dehydrodicatechins.Detailed chemical and physical characterizations further confirmed the novel FFs as flavonoids.Mechanistic investigations demonstrated that FP polymerizes flavan-3-ols and flav-2-en-3-ol carbocation,forming dimeric or oligomeric flaven-4→8-flavans,which we term“papanridins.”Data from transgenic experiments,mutant analysis,metabolic profiling,and phylogenetic analyses show that the biosynthesis of papanridins is prevalent in cacao,grape,blueberry,corn,rice,Arabidopsis,and other species in the plant kingdom.In summary,our study discoveries a group of novel oligomeric flavonoids,namely papanridins,and reveals that a novel FP-mediated polymerization mechanism for the biosynthesis of papanridins in plants.

款冬花中抑制肺癌细胞LA795增殖的活性成分研究

分析研究了款冬花中具有抑制肺癌细胞增殖的活性成分.以小鼠肺腺癌LA795细胞为体外抑瘤筛选模型,利用四甲基偶氮唑盐(MTT)比色法,结合硅胶柱色谱,Sephadex LH-20,PHPLC等手段追踪分离款冬花抗肺癌的活性成分.并通过理化和波谱分析方法鉴定了单体化合物的结构.它们分别是:1,2-di-(3′,4′-dihydroxycinnamoyl)-cychopenta-3-ol,(Ⅰ)、芦丁(Rutin,Ⅱ)、山奈酚(Kaemferol,Ⅲ)、槲皮素(Quercetin,Ⅳ)、异槲皮苷(Isoquercitrin,Ⅴ).其中(Ⅰ)为新化合物,化合物(Ⅴ)为首次从款冬花中分离得到.并采用MTT法对分得的化合物进行抑制LA795细胞株增殖作用的研究,用半数抑制浓度(IC)评价其抗肿瘤活性.结果表明化合物Ⅰ,Ⅲ,Ⅳ对小鼠肺腺癌细胞LA795的增殖都显示出一定的抑制作用.其中化合物Ⅰ和Ⅳ抑瘤作用较显著.IC50分别为125.2和83.2μg/mL.这些化合物抗肺癌细胞增殖活性为款冬花中首次发现.