Monoterpenoid indole alkaloids from Alstonia rostrata

Four new monoterpenoid indole alkaloids,alstrostines C-F together with thirteen known alkaloids were isolated from the leaves and twigs of Alstonia rostrata.All structures of new compounds were elucidated based on NMR,FTIR,UV,and MS spectroscopic data.Alstrostines C-E might originate from keto-enol tautomerism of preakummicine during biogenetic pathway of akummicine.

A new monoterpenoid indole alkaloid from Rauvolfia yunnanensis

One new monoterpenoid indole alkaloid, l l-methoxyburnamine-17-O-3′,4′,5′-trimethoxybenzoate （1）, was isolated from Rauvolfia yunnanensis Tsiang. Its structure was identified by speclroscopic evidences.

Putative Mode of Action of the Monoterpenoids Linalool, Methyl Eugenol, Estragole, and Citronellal on Ligand-Gated Ion Channels

Essential oil has been used as sedatives,anticonvulsants,and local anesthetics in traditional medical remedies;as preservatives for food,fruit,vegetable,and grain storage;and as bio-pesticides for food production.Linalool(LL),along with a few other major components such as methyl eugenol(ME),estragole(EG),and citronellal,are the active chemicals in many essential oils such as basil oil.Basil oil and the aforementioned monoterpenoids are potent against insect pests.However,the molecular mechanism of action of these chemical constituents is not well understood.It is well-known that the c-aminobutyric acid type A receptors(GABAARs)and nicotinic acetylcholine receptor(nAChR)are primary molecular targets of the synthetic insecticides used in the market today.Furthermore,the GABAAR-targeted therapeutics have been used in clinics for many decades,including barbiturates and benzodiazepines,to name just a few.In this research,we studied the electrophysiological effects of LL,ME,EG,and citronellal on GABAAR and nAChR to further understand their versatility as therapeutic agents in traditional remedies and as insecticides.Our results revealed that LL inhibits both GABAAR and nAChR,which may explain its insecticidal activity.LL is a concentration-dependent,noncompetitive inhibitor on GABAAR,as the half-maximal effective concentration(EC50)values of c-aminobutyric acid(GABA)for the rat a1b3c2L GABAAR were not affected by LL:(36.2±7.9)lmol-1 and(36.1±23.8)μmol·L-1 in the absence and presence of 5 mmol·L-1 LL,respectively.The half-maximal inhibitory concentration(IC50)of LL on GABAAR was approximately 3.2 mmol·L-1.Considering that multiple monoterpenoids are found within the same essential oil,it is likely that LL has a synergistic effect with ME,which has been previously characterized as both a GABAAR agonist and a positive allosteric modulator,and with other monoterpenoids,which offers a possible explanation for the sedative and anticonvulsant effects and the insecticidal activities of LL.

Hybrid Monoterpenoid Indole Alkaloids Obtained as Artifacts from Rauvolfia tetraphylla

Five new hybrid monoterpenoid indole alkaloids bearing an unusual 2,2-dimethyl-4-oxopiperidin-6-yl moiety,namely rauvotetraphyllines F–H(1,3,4),17-epi-rauvotetraphylline F(2)and 21-epi-rauvotetraphylline H(5),were isolated from the aerial parts of Rauvolfia tetraphylla.Their structures were established by extensive spectroscopic analysis.The new alkaloids were evaluated for their cytotoxicity in vitro against five human cancer cell lines.

Acaricidal activities of some essential oils and their monoterpenoidal constituents against house dust mite,Dermatophagoides pteronyssinus (Acari:Pyroglyphidae)

The acaricidal activities of fourteen essential oils and fourteen of their major monoterpenoids were tested against house dust mites Dermatophagoides pteronyssinus. Five concentrations were used over two different time intervals 24 and 48 h under laboratory conditions. In general, it was noticed that the acaricidal effect based on LC50 of either essential oils or monoterpenoids against the mite was time dependant. The LC50 values were decreased by increasing of exposure time. Clove, matrecary, chenopodium, rosemary, eucalyptus and caraway oils were shown to have high activity. As for the monoterpenoids, cinnamaldehyde and chlorothymol were found to be the most effective followed by citronellol. This study suggests the use of the essential oils and their major constituents as ecofriendly biodegradable agents for the control of house dust mite, D. pteronyssinus.

A chromosome-level genome assembly reveals that a bipartite gene cluster formed via an inverted duplication controls monoterpenoid biosynthesis in Schizonepeta tenuifolia

Biosynthetic gene clusters(BGCs)are regions of a genome where genes involved in a biosynthetic pathway are in proximity.The origin and evolution of plant BGCs as well as their role in specialized metabolism remain largely unclear.In this study,we have assembled a chromosome-scale genome of Japanese catnip(Schizonepeta tenuifolia)and discovered a BGC that contains multiple copies of genes involved in four adjacent steps in the biosynthesis of p-menthane monoterpenoids.This BGC has an unprecedented bipartite structure,with mirrored biosynthetic regions separated by 260 kilobases.This bipartite BGC includes identical copies of a gene encoding an old yellow enzyme,a type of flavin-dependent reductase.In vitro assays and virus-induced gene silencing revealed that this gene encodes the missing isopiperitenone reductase.This enzyme evolved from a completely different enzyme family to isopiperitenone reductase from closely related Mentha spp.,indicating convergent evolution of this pathway step.Phylogenomic analysis revealed that this bipartite BGC has emerged uniquely in the S.tenuifolia lineage and through insertion of pathway genes into a region rich in monoterpene synthases.The cluster gained its bipartite structure via an inverted duplication.The discovered bipartite BGC for p-menthane biosynthesis in S.tenuifolia has similarities to the recently described duplicated p-menthane biosynthesis gene pairs in the Mentha longifolia genome,providing an example of the convergent evolution of gene order.This work expands our understanding of plant BGCs with respect to both form and evolution,and highlights the power of BGCs for gene discovery in plant biosynthetic pathways.

Chromosome-level assembly and analysis of the Thymus genome provide insights into glandular secretory trichome formation and monoterpenoid biosynthesis in thyme

Thyme has medicinal and aromatic value because of its potent antimicrobial and antioxidant properties.However,the absence of a fully sequenced thyme genome limits functional genomic studies of Chinese native thymes.Thymus quinquecostatus Celak.,which contains large amounts of bioactive monoterpenes suchas thymol and carvacrol,is an important wild medicinal and aromatic plant in China.Monoterpenoids are abundant in glandular secretory trichomes.Here,high-fidelity and chromatin conformation capture technologies were used to assemble and annotate the T.quinquecostatus genome at the chromosome level.The 13 chromosomes of T.quinquecostatus had a total length of 528.66 Mb,a contig N50 of 8.06 Mb,and a BUSCO score of 97.34%.We found that T.quinquecostatus had experienced two whole-genome duplications,with the most recent event occurring4.34 million years ago.Deep analyses of the genome,in conjunction with comparative genomic,phylogenetic,transcriptomic,and metabonomic studies,uncovered many regulatory factors and genes related to monoterpenoids and glandular secretory trichome development.Genes encoding terpene synthase(TPS),cytochrome P450 monooxygenases(CYPs),short-chain dehydrogenase/reductase(SDR),R2R3-MYB,and homeodomain-leucine zipper(HD-ZIP)IV were among those present in the T.quinquecostatus genome.Notably,Tq02G002290.1(TqTPS1)was shown to encode the terpene synthase responsible for catalyzing production of the main monoterpene product g-terpinene from geranyl diphosphate(GPP).Our study provides significant insight into the mechanisms of glandular secretory trichome formation and monoterpenoid biosynthesis in thyme.This work will facilitate the development of molecular breeding tools to enhance the production of bioactive secondary metabolites in Lamiaceae.

Discovery of Natural Co-occurring Enantiomers of Monoterpenoid Indole Alkaloids

Main observation and conclusion Two new pairs of monoterpenoid indole alkaloids(MIAs)enantiomers as well as their new congeners were isolated from stems of Tabernaemontana bovina Lour.(Apocynaceae).Their structures were elucidated by spectroscopic analyses and confirmed by X-ray diffractions and computational calculations.Tabovine A,tabovine B and tabovines C-D possessed unprecedented 6/5/5/6/6,6/5/5/6/5 and 6/5/6/6/6 ring systems,respectively.It is the first time to report co-occurring enantiomers of MIAs.Additionally,the explanation concerning biogenesis of MIAs was provided.The findings would open a new window where we could disclose more diverse MIAs.

Monoterpenoid Indole Alkaloids with Promoting Neurite Growth from Tabernaemontana divaricata

Phytochemical investigations on Tabernaemontana divaricata led to the isolation of seven undescribed monoterpenoid indole alkaloids,taberdicatines A-G(1-7).Taberdicatines A-C might be derived from Aspidosperma-type alkaloid,less skeletal carbons in 1-2 and an additional carbon in 3.Taberdicatines D-E(4-5)were attributed to Iboga alkaloids with enantiomeric skeleton,respectively.Alkaloid 3 could promote the neurite growth of mouse primary cortical neurons at the concentration of 5 pimol/L.

一种白腐真菌生物学特性及萜类化合物对其防治研究

白腐真菌是影响木材生长主要病原菌之一,本文对白腐真菌的最适培养基、碳源、氮源、温度、pH值和致死温度,以及几种单萜类化合物对其抑菌效果进行研究。结果表明,白腐真菌落生长的最佳培养基为PDA,碳源以甘露醇、氮源以牛肉膏为宜,最适pH值为6,最适温度为35℃,而致死温度为51℃。β-香茅醇和乙酸橙花酯对白腐真菌具有显著的抑菌效果,β-香茅醇浓度为45μL/mL时,对白腐真菌的抑菌率为84.1%;乙酸橙花酯浓度为90μL/mL时,抑菌率为82%。

风轮菜中1个新的单萜

目的:研究风轮菜中的化学成分及生物活性。方法:运用硅胶、十八烷基硅烷键合硅胶(ODS)、Sephadex LH-20柱色谱及半制备高效液相色谱等方法,对风轮菜地上部分70%乙醇提取物的正丁醇萃取部位进行分离纯化。采用高分辨质谱、核磁共振波谱、紫外色谱、红外色谱、圆二色谱和计算圆二色谱对新化合物进行结构鉴定,核磁共振波谱和质谱鉴定已知化合物。采用棕榈酸(PA)诱导的HepG2细胞损伤模型研究化合物1、6和9的细胞保护活性。结果:从风轮菜70%乙醇提取物的正丁醇萃取部位中分离得到9个化合物,分别鉴定为(4S,9S)-9-羟基茉莉酮(1)、红花菜豆酸(2)、环-(S-脯氨酸-R-亮氨酸)(3)、芹菜素-7-O-β-D-葡萄糖醛酸甲酯(4)、2-甲氧基-4-(2-丙烯基)-苯基-β-D-吡喃葡萄糖苷(5)、吐叶醇(6)、柚皮素-7-O-β-D-葡萄糖醛酸(7)、对-薄荷-3,8-二烯-1,2-二醇(8)、黄麻香堇醇C (9)。与模型组细胞存活率[(63.5±2.3)%]相比,化合物9低、中、高剂量组细胞存活率[(81.0±2.0)%、(83.4±1.8)%、(90.8±2.1)%]差异有统计学意义(P<0.001);化合物6高剂量组细胞存活率[(72.3±2.2)%]差异有统计学意义(P<0.05);化合物1未表现出明显活性。结论:化合物1为新化合物,化合物2~3、5~6和8系首次从风轮菜中分离得到。化合物9对PA诱导的HepG2细胞损伤具有显著的细胞保护活性,且与剂量呈正相关。化合物6在高剂量有一定的细胞保护活性。

云南山橙果实中的生物碱类成分研究

目的 研究夹竹桃科云南山橙(Melodinus yunnanensis)果实的生物碱成分。方法 利用硅胶、ODS、Sephadex LH-20等柱色谱技术及薄层色谱、制备液相色谱等方法进行分离、纯化,根据化合物的理化性质及波谱学数据鉴定其化学结构。结果 从云南山橙果实中分离获得21个生物碱类成分,化合物1为新化合物,命名为meloyunnanine D (1),化合物1-21分别鉴定为:meloyunnanine D (1), scandine (2), scandine N-oxide (3),10-hydroxyscandine (4), tabersonine (5), 11-methoxytabersonine (6), 11-hydroxytabersonine (7), lochnericine (8),pachysiphine (9), 11-hydroxylochnericine (10), 19R-hydroxytabersonine (11), 19R-acetoxytabersonine (12),voaphylline (13), 19S-vindolinine (14), 19R-vindolinine (15), venalstonidine (16), 17α-hydroxyvenalstonine (17),19R-methoxytubotaiwine (18), kopsiyunnanines F1 (19), stemmadenine-N-oxide (20), stemmadenine (21)。结论 系统地认识了云南山橙果实中的生物碱成分,从中分离得到21个化合物,其中化合物1-4属于单萜喹啉型生物碱,化合物5-19属于白坚木碱型生物碱,化合物20-21属于士的宁碱型生物碱。其中3-4, 7-12, 14-21均为首次从该植物中分离得到。

室内空气中单萜类化合物检测方法的研究

Monoterpenoids are widely existing in indoor air.A GC-MS method was established for determination of monoterpenoids in the indoor air by using silonite coated canisters(SUMMA canisters),and preconcentrating low level samples utilizing three stages focuser.The method was suitable for the determination of trace VOCs in indoors air.The detection limits of method for α-pinene and β-pinene were both 0.71 μg/m3.

川芎化学成分研究

目的：对伞形科藁本属植物川芎Ligusticum chuanxiong干燥的根茎进行化学成分研究。方法：川芎的干燥根茎用水提取，依次用醋酸乙酯，正丁醇萃取，对醋酸乙酯部分采用各种柱色谱进行分离纯化，通过波谱数据分析进行结构鉴定。结果：从醋酸乙酯部分分离11个化合物，分别鉴定为：（4s）-p—menth-1-ene-4，7diol（1），aromadendrane-4α，10β-diol（2），aromadendrane-4α，10α—diol（3），aromadendrane-4β，10β-diol（4），augusfic acid（5），川芎三萜（xiongterpene，6），孕（甾）烯醇酮（pregnenolone，7），镰叶芹二醇[3（R），8（S），9（Z）-falcarindiol，8]，洋川芎内酯F（senkyunolide F，9），洋川芎内酯I（senkyunolideI，10），4-羟基-3-丁基苯肽（4-hydroxyl-3-butylphthalide，11）。结论：化合物1～5为首次从该种中分离得到。

天山棱子芹化学成分的研究(英文)

从天山棱子芹中首次分离得到15个已知化合物,通过NMR、MS及IR等波谱数据,分别鉴定为6,7二羟基香豆素(1),(+)marmesin(2),marmesinin(3),5,7,4′三羟基黄酮(4),莰非醇3OαL吡喃鼠李糖甙(5),藤黄菌素3′OβD吡喃葡萄糖甙(6),(R)6hydroxy3(2hydroxypropan2yl)6methylcyclohex2enone(7),4羟基苯甲酸(8),3甲氧基4羟基苯甲酸(9),3甲氧基4,5亚甲二氧基苯甲酸(10),丁香酸甲酯(11),丁香酸甲酯4OβD吡喃葡萄糖甙(12),姜油酮4′OβD吡喃葡萄糖甙(13),2(4羟基苯基)乙醇(14)和正二十八醇(15)。其中化合物7为一新的天然产物。

沙冬青地上部分的化学成分研究

目的:研究沙冬青Ammopiptanthus mongolicus地上部分的化学成分。方法:应用硅胶和Sephadex LH-20凝胶柱色谱法以及高效液相色谱法对其化学成分进行分离,并利用NMR和MS等方法鉴定化合物。结果:从沙冬青的干燥地上部分中分离得到10个化合物,分别鉴定为间羟基苯甲酸(1),对羟基苯乙酮(2),β-谷甾醇(3),(-)-丁香脂素(4),(+)-落叶松脂醇(5),blumenol A(6),blumenol B(7),β-胡萝卜苷(8),松柏苷(9),丁香苷(10)。结论:该10个化合物均为首次从沙冬青属植物中分离得到。

合欢皮化学成分的分离鉴定

目的 :研究合欢皮的化学成分。方法 :用色谱法和波谱方法对合欢皮的化学成分进行分离和结构鉴定。结果 :共得到 5个化合物 :(- ) 丁香树脂酚 4 O β D 呋喃芹糖基 (1→ 2 ) β D 吡喃葡萄糖苷 (1)、(6R) 2 反式 2 ,6 二甲基 6 O β D 吡喃鸡纳糖基 2 ,7 辛二烯酸 (2 )、(6S) 2 反式 2 ,6 二甲基 6 O β D 吡喃鸡纳糖基 2 ,7 辛二烯酸(3 )、5 ,5′ dimethoxy 7 oxolariciressinol(4)和 ( ) 丁香树脂酚 (5 )。 结论 :化合物 2 ,3和

几种单环单萜化合物在农药中的应用

综述几种典型单环单萜柠檬烯、紫苏醛、薄荷酮、香芹酮、薄荷醇等化合物在农药中应用及其研究进展,包括对螨虫、线虫、伊蚊、桉蚊、库蚊等的驱避、毒杀作用和对甲虫、松树象鼻虫等的拒食作用。以及对大肠杆菌、伤寒沙门氏菌、李氏特菌、弧菌等菌的杀菌作用和对马铃薯、郁金香等抑制生长作用。

北五味子中的一个新单萜苷

The fruits of Schisandra chinensis(Turcz.) Baill. is a traditional Chinese medicine for treatment of cough, dyspnea, insomnia and chronic hepatitis. During our investigation of Schisandra chinensis collected in Liaoning province, the water soluble extract of Schisandra chinensis(Turcz.) Baill was found to possess a strong activity on cardiovascular system. Some water soluble chemical constitutents from this species were reported in our earlier paper. In continuation of our studies on the seeds of Schisandra chinensis, a new monoterpenoid glycoside, named Schisanchinin A(1), was isolated from the water soluble extract through column chromatography. The spectroscopic and chemical evidences revealed its structure to be p-menthane-1,8,9-triol 9-O-β-D-glucopyranoside(1).

气相色谱-质谱联用分析茵陈与牛至挥发油的化学成分

目的分析茵陈和牛至中挥发油成分,并比较其异同。方法按2010年版《中国药典》附录[挥发油测定法]中的规定,提取茵陈和牛至中的挥发油,用气相色谱-质谱法分析检测。结果茵陈和牛至挥发油的主要成分均为单萜类、双环倍半萜类成分。该两类成分在茵陈挥发油中质量分数分别为31.31%、68.69%;在牛至挥发油中质量分数分别为69.31%、20.25%。其中单萜类成分中两者共有成分的含量分别为17.89%、44.46%;双环倍半萜类成分中两者共有成分的含量分别为21.07%、14.0%。结论茵陈和牛至的挥发油中含有一些相同成分,但含量有较大差异。