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1.
Yoshinori Asakawa Masao Yoyota Tsunematsu Takemoto Isao Kubo Koji Nakanishi 《Phytochemistry》1980,19(10):2147-2154
The characteristic pungency of the liverworts Plagiochila species P. fruticosa, P. hattoriana, P. ovalifolia and P. yokogurensis is due to a new ent-secoaromadendrane-type sesquiterpene hemiacetal, plagiochiline A, which exhibits very strong antifeedant activity against the African army worm, Spodoptera exempta at 1–10ng/cm2. Two new secoaromadendranes, plagiochilide and furanoplagiochilal A, together with the previously known plagiochiline C were isolated from P. yokogurensis. Plagiochilal A, which may be a precursor of plagiochilide and its related hemiacetals, and a bitter principle, plagiochiline B were also isolated from P. hattoriana. P. ovalifolia contained plagiochilines A, B and C. From P. fruticosa, plagiochilide and plagiochilines A, B and C were isolated. The structures of the new secoaromadendrane-type sesquiterpenes were elucidated by extensive 1H NMR and 13CNMR studies. 相似文献
2.
Zohreh Habibi Rasool Kheyrabadi Sabrieh Ghasemi Maryam Yousefi Seik Weng Ng 《Phytochemistry letters》2012,5(4):705-707
A new eudesmane-type sesquiterpenoid together with two known flavonoids were isolated from the chloroform extract of the aerial part of Sclerorhachis platyrachis. The structure of the new compound was deduced from its comprehensive spectroscopic analysis including IR, EI-MS, 1H NMR, 13C NMR, DEPT, COSY, HMBC and HMQC and was shown to be 4R*-hydroxy-6S*-tigloyloxyeudesma-7S*-11 (13)-en-12-oic acid (1). Finally, the structure of the new compound was unambiguously confirmed by single-crystal X-ray analysis. The structure of known compounds 2 and 3 were identified by comparison of their spectral data with those reported in the literature. 相似文献
3.
《Phytochemistry》1986,25(4):891-897
The aerial parts of Artemisia iwayomogi afforded, in addition to already known terpenes, eleven new cudesmanolides whereas four new guaianolides were found in A. gmelinii. No sesquiterpene lactones were detected in the aerial parts of A. santolinifolia which afforded two new nerolidol derivatives besides several other already known compounds. From A. caerulescens var. cretacea six eudesmanolides were isolated, one of which has not been reported previously. The structures were elucidated by high field 1H NMR spectroscopy and chemical transformations. The chemotaxonomic significance of sesquiterpene lactones within the section Abrotanum and the subgenus Seriphidium is briefly discussed. 相似文献
4.
《Phytochemistry》1986,25(7):1663-1667
The aerial parts of Artemisia douglasiana afforded, in addition to some known sesquiterpene lactones, 22 new closely related guaianolides. A new thiophene acetylene was isolated from the aerial parts of A. schmidtiana together with some known sesquiterpene lactones. The structures were elucidated by high field 1H NMR spectroscopy. 相似文献
5.
Mutants at 2 new loci which control mutagen-sensitivity are described. Mutants at both loci are female-sterile and are hypersensitive to killing by MMS; neither increases the frequency of sex-linked recessive lethals. A screen of previously described female-sterile and meotic mutants has revealed that a number of these are also sensitive to mutagens. In addition, several new mutants have been identified on the basis of sensitivity to either HN2 or MMS. An anlysis of complementation data suggests that all of the X-linked genes controlling sensitivity to MMS may now have been identified. Among the new mei-41 alleles are mutants which show verly little meiotic nondisjunction or loss. Cytogenetic mapping of previously known mutants is also described. The mutants mus(1)104D1 and mei-41D5 are located in th eregion 14B13±?14D1,2 on the polytene chromosome map, and they map very close to each other genetically. Cytogenetically mus(1)101D1 is between salivary chromosome bands 12A6,7 and 12D3, mus(1)103D1 is between bands 12A1,2 and 12A6,7, and mus(1)-109A1 is in section 8F3-9A2. 相似文献
6.
Shin-Ichi Hatanaka Yoko Murooka Koshi Saito Yumiko Shida Yoshito Takeuchi 《Phytochemistry》1982,21(2):453-454
A new amino acid, E-2(S)-amino-3-methyl-3-pentenoic acid was isolated from Coniogramme intermedia. The structure was elucidated by elementary analysis, optical rotation, catalytic hydrogenation, 1H and 13C NMR spectra. 相似文献
7.
In addition to a known derivative, five new coumarin-hemiterpene ethers were isolated from the leaves of Artemisia laciniata, A. armeniaca and A. tanacetifolia and identified by 1H NMR and, in part, by 13C NMR spectroscopy. The coumarin patterns are characterized particularly by compounds with a hydroxylated and saturated isoprenoid unit attached to oxygen at the C-8 position and by 5,7,8-trioxygenated derivatives. The chemotaxonomic significance of the coumarin-terpenoid ethers within Artemisia is discussed. 相似文献
8.
Xiaomei Wei Karinel Nieves Abimael D. Rodríguez 《Bioorganic & medicinal chemistry letters》2010,20(19):5905-5908
A new tetracyclic bis-piperidine alkaloid, neopetrosiamine A (1), has been extracted from the marine sponge Neopetrosia proxima collected off the west coast of Puerto Rico. The structure of compound 1 was elucidated by analysis of spectroscopic data coupled with careful comparisons of its 1H and 13C NMR data with those of a well-known 3-alkylbis-piperidine alkaloid model. The new alkaloid displayed strong in vitro cytotoxic activity against a panel of cancer cell lines as well as in vitro inhibitory activity against the pathogenic microbes Mycobacterium tuberculosis and Plasmodium falciparum. 相似文献
9.
A new ent-secoaromadendrane-type sesquiterpene hemiacetal, plagiochiline G, was isolated from Plagiochila ovalifolia. Four new ent-sesquiterpene hemiacetals, plagiochiline H and I, and two pungent methoxyplagiochilines A1, A2 and non-pungent methoxyplagiochiline C were also isolated from P. yokogurensis. The methoxylated plagiochilines A1, A2 and C were derived from the plagiochilines A and C during the extraction procedure. A new germacrene, ent-3α-acetoxybicyclogermacrene, ent-maaliol and the previously known ent- aromadendrane-type sesquiterpenes have been obtained from P. yokogurensis. The structures of the new compounds were elucidated by 1H NMR spectral data and by chemical correlation. 相似文献
10.
《Phytochemistry》1987,26(3):850-852
A new 3,4-seco-ambrosanolide was isolated from Ambrosia artemisiifolia and identified by means of spectroscopic evidence 1H and 13C NMR, IR and MS). 相似文献
11.
Alcaligenes defragrans strains denitrify on monoterpenes with an unsaturated hydrocarbon structure. A new cometabolic reaction, the formation of isoterpinolene from isolimonene, was detected in cultures that grew on a monoterpene. The biotransformation of isolimonene, a monocyclic monoterpene with a sp3-hybridized C1 atom of the menthane skeleton, contrasts with the complete mineralization of monoterpenes with a sp2-hybridized C1 atom. This selectivity indicates a demand for a sp2-hybridized C1 atom as structural property for monoterpenes that can be oxidized by A. defragrans. 相似文献
12.
A new clerodane derivative was isolated from Teucrium polium var. polium. The structure and stereochemistry have been established by detailed studies of the 1H NMR spectra. 相似文献
13.
A new diol glucoside, 2-β-d-glucopyranosyloxy-2-methylpropanol, the first reported naturally occurring monoglucoside of an aliphatic dihydric alcohol, was isolated from pods of Acacia sieberana var. woodii. Structure elucidation was based on 1 H and 13C NMR spectroscopy, and enzymatic analyses. The compound was hydrolysed very slowly by almond β-glucosidase, but cleaved by a β-glucuronidase enzyme complex from Helix pomatia. 相似文献
14.
Figueras MJ Collado L Levican A Perez J Solsona MJ Yustes C 《Systematic and applied microbiology》2011,34(2):105-109
Nineteen bacteria isolates recovered from shellfish samples (mussels and oysters) showed a new and specific 16S rDNA-RFLP pattern with an Arcobacter identification method designed to recognize all species described up to 2008. These results suggested that they could belong to a new species. ERIC-PCR revealed that the 19 isolates belonged to 3 different strains. The sequence of the 16S rRNA gene of a representative strain (F98-3T) showed 97.6% similarity with the closest species Arcobacter marinus followed by Arcobacter halophilus (95.6%) and Arcobacter mytili (94.7%). The phylogenetic analysis with the16S rRNA, rpoB, gyrB and hsp60 genes placed the shellfish strains within the same cluster as the three species mentioned (also isolated from saline habitats) but they formed an independent phylogenetic line. The DDH results between strain F98-3T and A. marinus (54.8% ± 1.05), confirmed that it represents a new species. Several biochemical tests differentiated the shellfish isolates from all other Arcobacter species. Although the new species was different from A. mytili, they shared not only the same habitat (mussels) but also the characteristic of being so far the only Arcobacter species that are simultaneously negative for urea and indoxyl acetate hydrolysis. All results supported the classification of the shellfish strains as a new species, for which the name Arcobacter molluscorum sp. nov. with the type strain F98-3T is proposed (=CECT 7696T = LMG 25693T). 相似文献
15.
A new natural product, 3,4,8,9,10-pentahydroxy-dibenzo-[b,d]pyran-6-one was isolated from the flowers of Tamarix nilotica which also contains the known compound ellagic acid, 2,3,7,8-tetrahydroxy [1]benzopyrano[5,4,3-cde][1]benzopyran-5,10-dione. The structure of the new compound was determined by chemical and spectroscopic methods. The 13C MNR spectrum of ellagic acid was recorded and assigned. 相似文献
16.
In addition to the known p-coumaric acid, the furanofuran lignan (±)-syringaresinol and the digalloylglucose, nilocitin, were obtained from the whole plant of Ephedra alata. A new natural alkaloid, ephedralone, was also isolated. The structures were determined mostly by mass, 1H and 13CNMR spectroscopy. 相似文献
17.
Yong Xiao Lunlin Chen Jun Zou Entang Tian Wei Xia Jinling Meng 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2010,121(6):1141-1150
Intersubgenomic heterosis in rapeseed has been revealed in previous studies by using traditional Brassica napus (AnAnCnCn) to cross partial new type B. napus with Ar/Cc introgression from the genomes of B. rapa and B. carinata, respectively. To further enlarge the genetic basis of B. napus and to facilitate a sustained heterosis breeding in rapeseed, it is crucial to create a population for substantial new type B. napus diversified at both A/C genomes. In this experiment, hundreds of artificial hexaploid plants (ArArBcBcCcCc) involving hundreds of B. carinata/B. rapa combinations were first crossed with elite lines of partial new type B. napus. The pentaploid plants (AABCC) were open-pollinated in isolated conditions, and their offspring were successively self-pollinated and intensively selected for two generations. Thereafter, a population of substantial new type B. napus mainly with a genomic composition of ArArCcCc harbouring genetic diversity from 25 original cultivars of B. rapa and 72 accessions of B. carinata was constructed. The population was cytologically verified to have the correct chromosome constitution of AACC and differed genetically from traditional B. napus, in terms of the genome components of Ar/Cc and Bc as well as the novel genetic variations induced by the interspecific hybridisation process. Synchronously, rich phenotypic variation with plenty of novel valuable traits was observed in the population. The origin of the novel variations and the value of the population are discussed. 相似文献
18.
《Inorganica chimica acta》1986,125(4):203-206
A new metal chelating moiety, 4-ethylamido [5,(2′- thienyl)-2-thiophene]imidazole iron(II) (1) was synthesized and showed antitumor activity in vitro. The bisthiophene moiety which sterically resembles the bithiazole units of bleomycin may allow us to probe further the mechanism of antitumor action by bleomycin. The cyclic voltammetry for the new compound 1 in DMSO showed a nearly reversible Fe3+/Fe2+ transition. The electron spin resonance spectrum consisted of a fairly broad band resonance centered at g = 2.00989, similar to that of a bleomycin-Fe2+ complex. The new compound 1 causes cleavage of double helical DNA without the requirement of an extra intercalating group. 相似文献
19.
Multiple GATA factors – regulatory proteins with consensus zinc finger motifs that bind to DNA elements containing a GATA core sequence – exist in the filamentous fungus Neurospora crassa. One GATA factor, NIT2, controls nitrogen metabolism, whereas two others, WC-1 and WC-2, regulate genes responsive to blue light induction. A gene encoding a new GATA factor, named SRE, was isolated from Neurospora using a PCR-mediated method. Sequence analysis of the new GATA factor gene revealed an ORF specifying 587 amino acids, which is interrupted by two small introns. Unlike all previously known Neurospora GATA factors, which possess a single zinc-finger DNA-binding motif, SRE contains two GATA-type zinc fingers. The deduced amino acid sequence of SRE shows significant similarity to URBS1 of Ustilago and SREP of Penicillium. A loss-of-function mutation was created by the RIP procedure. Analysis of sre + and sre ? strains revealed that SRE acts as a negative regulator of iron uptake in Neurospora by controlling the synthesis of siderophores. Siderophore biosynthesis is repressed by high iron concentrations in the wild-type strain but not in sre ? mutant cells. The sre promoter contains a number of GATA sequences; however, expression of sre mRNA occurs in a constitutive fashion and is not regulated by the concentration of iron available to the cells. 相似文献
20.
《Gene》1998,212(2):179-188
A new Bacillus subtilis sporulation-specific gene, yhcN, has been identified, the expression of which is dependent on the forespore-specific sigma factor σG and to a much lesser extent on σF. A translational yhcN-lacZ fusion is expressed at a very high level in the forespore, and the protein encoded by yhcN was detected in the inner spore membrane. A yhcN mutant sporulates normally and yhcN spores have identical resistance properties to wild-type spores. However, the outgrowth of yhcN spores is slower than that of wild-type spores. 相似文献