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1.
Mexiprostil is a new gastroprotective 16-methoxy-16-methyl-PGE1 methyl ester. To assign the absolute configuration at C-15, a crystalline high-melting C-1 ester analog 5 11,15-dihydroxy-16-methoxy-16-methyl-9-oxoprost-13-en-1-oic acid 4-(4-bromobenzamide)phenyl ester (15R, 16R) was prepared and submitted to single crystal X-ray analysis. Since C-8, C-11, C-12 and C-16 are shown to have R configurations, the X-ray diffraction results established that the configuration at C-15 is also R.  相似文献   

2.
Chemical examination of the seeds of Chinese yew, Taxus yunnanensis Cheng et L. K. Fu resulted in the isolation of an 11(15-->1)abeotaxane, an 11(15-->1), 11(10-->9)bisabeotaxane and two 3,11-cyclotaxanes. The structures of these new taxoids were established as 13alpha-acetoxy-5alpha-cinnamoyloxy-11(15-->1)abeotaxa-4(20),11-diene-9alpha,10beta,15-triol (1), 20-acetoxy-2alpha-benzoyloxy-4alpha, 5alpha, 7beta, 9alpha, 13alpha-pentahydroxy-11(15-->1), 11(10-->9) bisabeotax-11-eno-10,15-lactone (2), 2alpha,10beta-diacetoxy-5alpha-cinnamoyloxy-9alpha-hydroxy-3,11 -cyclotax-4(20)-en-13-one (3) and 10beta-acetoxy-2alpha,5alpha,9alpha-trihydroxy-3,11-cyclotax-4(20)-en-13-one (4) on the basis of spectral analyses.  相似文献   

3.
Chemical examination of the hexane extract of the roots of Excoecaria agallocha Linn collected from the Godavari estuary resulted in the isolation of altogether eleven diterpenoids of which five (1-5) are new. The structures of the new diterpenoids have been elucidated by a study of their physical and spectral (UV, IR, 1H, 13C, DEPT, 1H-1H COSY, NOESY, HMQC, HMBC and MASS) data as 3-oxo-ent-13epi-8(13)-epoxy-15-chloro-14-hydroxylabdane (1), ent-15-chloro-13,14-dihydroxylabd-8(9)-en-3-one (2), ent-15-chloro-labd-8(9)ene-3alpha,13,14-triol (3), ent-11beta-hydroxy-8(14),15-isopimaradien-3-one (4), 8,13-epoxy-3-nor-2,3-seco-14-epilabden-2,4-olide (5). The six known diterpenoids have been characterised respectively as ent-3-oxo-13-epi-manoyl oxide (6), ent-3beta-hydroxy-13-epi-manoyl oxide (7), (13R,14S)-ent-8alpha,13;14,15-diepoxy-13-epi-labdan-3-one (8), ent-16-hydroxy-3-oxo-13-epimanoyl oxide (9), ent-15-hydroxylabda-8(17),13E-dien-3-one (10), labda-8(17),13E-diene-3beta,15-diol (11) by a comparative study of their spectral data with the literature values.  相似文献   

4.
Gametophytic self-incompatibility in plants involves rejection of pollen when pistil and pollen share the same allele at the S locus. This locus is highly multiallelic, but the mechanism by which new functional S alleles are generated in nature has not been determined and remains one of the most intriguing conceptual barriers to a full understanding of self-incompatibility. The S(11) and S(13) RNases of Solanum chacoense differ by only 10 amino acids, but they are phenotypically distinct (i.e., they reject either S(11) or S(13) pollen, respectively). These RNases are thus ideally suited for a dissection of the elements involved in recognition specificity. We have previously found that the modification of four amino acid residues in the S(11) RNase to match those in the S(13) RNase was sufficient to completely replace the S(11) phenotype with the S(13) phenotype. We now show that an S(11) RNase in which only three amino acid residues were modified to match those in the S(13) RNase displays the unprecedented property of dual specificity (i.e., the simultaneous rejection of both S(11) and S(13) pollen). Thus, S(12)S(14) plants expressing this hybrid S RNase rejected S(11), S(12), S(13), and S(14) pollen yet allowed S(15) pollen to pass freely. Surprisingly, only a single base pair differs between the dual-specific S allele and a monospecific S(13) allele. Dual-specific S RNases represent a previously unsuspected category of S alleles. We propose that dual-specific alleles play a critical role in establishing novel S alleles, because the plants harboring them could maintain their old recognition phenotype while acquiring a new one.  相似文献   

5.
Diterpenes and sesquiterpenes from the bark of Taxus yunnanensis   总被引:3,自引:0,他引:3  
Two taxane-type diterpenes, 10beta-acetoxy-2alpha,5alpha,7beta,9alpha-tetrahydroxytaxa-4(20),11-dien-13-one and 2alpha-acetoxy-9alpha-benzoyloxy-5alpha,7beta,10beta,15-tetrahydroxy-11(15-->1)- abeotaxa-4(20),11-dien-13-one, and two new drimane-type sesquiterpenes, 1beta-acetoxy-7-drimen-11alpha-ol-12,11-lactone and 1beta-acetoxy-11,12-epoxy-6-drimen-8alpha,11alpha-diol, were isolated from the bark of Taxus yunnanensis together with 35 known taxane-type diterpenes, a known drimane-type sesquiterpene and a known flavanone.  相似文献   

6.
Fifty-eight new anonymous simple sequence repeats (SSR) were generated and mapped to various rat chromosomes. Among them two genes (rat homologs for human cadherin-14 and mouse fibroblast growth factor-related protein) were mapped on Chromosomes (Chrs) 2 and 11 respectively. The majority of markers were generated from a small insert genomic library specific to Chr 11, 13, 14, and 15. Twenty new markers were mapped to Chr 13, which is known to contain a blood pressure quantitative trait locus (QTL). Several approaches to obtain microsatellite markers are described. The protocols and newly generated markers should be useful for ongoing rat genome project. Received: 24 April 1998 / Accepted: 23 June 1998  相似文献   

7.
Starting from the D-homo lactones of androst-4-en-3-one 3 and 4, prepared from 1 and 2, the new 17a homolactones 5-12, 14 and 15, were synthesized. The 4-hydroxy compounds 9 and 10 were obtained through the reaction of 4alpha,5alpha- (5 and 7) and 4beta,5beta- (6 and 8) epoxides with formic acid. The epoxides 5 and 6 were prepared from compound 3, and epoxides 7 and 8 from compound 4 by oxidation with H(2)O(2) under basic conditions. Compound 1 served as a starting substance for obtaining lactones 11-13. Oxidation of compound 1 with m-chloroperbenzoic acid yielded 11 and 12, but compound 13 gave 14. Compound 15 was obtained from 13 by oxidation with H(2)O(2) under basic conditions. The structures of epoxides 6 and 14 were confirmed by X-ray structural analysis. Cytotoxic activity against three tumor cell lines (human breast adenocarcinoma ER+, MCF-7, human breast adenocarcinoma ER-, MDA-MB-231, and prostate cancer PC3) was evaluated. Compounds 6 and 14 showed strong activity against PC3, the IC(50) being 10.6 and 2.2 microM, respectively, whereas compounds 3 and 8 showed strong activity against MDA-MB-231 (IC(50) is 9.3 and 3.6 microM, respectively). Aromatase inhibition assay showed that the tested compounds 9, 10, and 14 possess lower activity compared to formestane.  相似文献   

8.
Thirteen eastern moles, Scalopus aquaticus, collected in West Texas were examined for coccidian oocysts; 11 (85%) were infected and eight (73%) of these had multiple infections representing two or more species. One cyclosporan, three eimerians, and two isosporans were studied and all are described as new species. Sporulated oocysts of Cyclospora megacephali n. sp. were subspheroidal, 18.5 X 15.7 (14-21 X 12-18) microns; they had sporocysts pointed at one end with Stieda bodies nearly as wide as the sporocysts themselves, and were 15.0 X 7.2 (11-17 X 6-9) microns; C. megacephali was found in four (31%) hosts. Sporulated oocysts of Eimeria scalopi n. sp. were spheroidal to subspheroidal, 13.6 X 12.6 (11-17 X 11-15) microns with sporocysts lemon-shaped, 8.7 X 5.5 (7-10 X 4-7) microns; it was found in six (46%) hosts. Sporulated oocysts of Eimeria aquatici n. sp. were asymmetrically ellipsoidal, 17.0 X 10.6 (14-20 X 9-14) microns with sporocysts elongately ovoidal, 9.0 X 5.2 (8-11 X 4-6) microns; it was found in two (15%) hosts. Sporulated oocysts of Eimeria motleiensis n. sp. were subspheroidal, 17.0 X 15.3 (15-20 X 13-18) microns with sporocysts ovoidal, 10.7 X 6.8 (10-13 X 6-8) microns; it was found in seven (54%) hosts. Sporulated oocysts of Isospora motleiensis n. sp. were spheroidal to subspheroidal, 13.6 X 12.0 (10-17 X 8-15) microns with sporocysts broadly ovoidal, 9.5 X 6.7 (7-11 X 4-8) microns; it was found in nine (69%) hosts. Sporulated oocysts of Isospora aquatici n. sp. were subspheroidal, 20.9 X 18.4 (15-24 X 13-21) microns with sporocysts ellipsoidal, 11.8 X 9.0 (9-14 X 7-11) microns; it was found in two (15%) hosts.  相似文献   

9.
A new triterpenoid, 22,29xi-epoxy-30-norhopane-13beta-ol (1) was isolated together with six known compounds viz., fern-9(11)-en-6alpha-ol. fern-9(11)-ene, fern-9(11)-en-25-oic acid, fern-9(11)-en-28-ol, filicenol-B, adiantone and oxidation product of fern-9(11)-en-6alpha-ol obtained as 6-oxofern-9(11)-ene from the whole plant of Adiantum lunulatum, and their structures were elucidated by means of spectroscopic analysis and antibacterial evaluation of these compounds were conducted.  相似文献   

10.
The structures of two new cyathane-type diterpenoids isolated from a liquid culture of Strobilurus tenacellus have been elucidated. The chemical structures of the new compounds 1 and 2 were identified as (12S)-11alpha,14alpha-epoxy-13alpha,14beta,15-trihydroxycyath-3-ene and (12R)-11alpha,14alpha-epoxy-13alpha,14beta,15-trihydroxycyath-3-ene, respectively, by spectral methods, including HR-EI-MS, and 1D- and 2D-NMR techniques. Compounds 1 and 2 show antimicrobial activity against Pseudomonas aeruginosa. In addition, both compounds were also tested for activity against human cancer cells, and 2 showed growth inhibitory activity against YMB and COLO 201 cells.  相似文献   

11.
Two new taxanes were isolated from the needles of Taxus canadensis. Their structures were established as 10beta,13alpha-diacetoxytaxa-4(20),11-diene-5alpha,9alpha,14beta-triol (1) and 4alpha,13alpha-diacetoxy-2alpha,20-epoxy-11(15-->1)abeotaxa-11,15-diene-5alpha,7beta,9alpha,10beta-tetraol (2) on the basis of a spectroscopic analysis.  相似文献   

12.
Two new taxanes were isolated from the MeOH extract of the needles and branches bark of the Japanese yew, Taxus cuspidata. The structures were established as (2alpha,5alpha,7beta,9alpha,10beta,13alpha)-5,10,13,20-tetraacetoxytax-11-ene-2,7,9-triol (1) and (2alpha,5alpha,9alpha,10beta)-2,9,10-triacetoxy-5-[(beta-D-glucopyranosyl)oxy]-3,11-cyclotax-11-en-13-one (2) on the basis of in-depth 1D- and 2D-NMR analyses. Compound 2 is the first example of a transannular taxane glycoside isolated from a natural source.  相似文献   

13.
A panel of 36 hamster-bovine hybrid cell lines was used to assign 15 bovine microsatellites. Locus identification, synteny group and/or chromosome assignment and registration number were as follows: ILSTS001 (U22, Chr07, D7S13), ILSTS002 (U09, Chr18, D18S7), ILSTS004 (U10, Chr01, D1S28), ILSTS005 (U05, Chr10, D10S25). ILSTS006 (U22, Chr07, D7S8), ILSTS008 (U24, Chr14, D14S15), ILSTS010 (U27, DU27S11), ILSTS011 (U24, Chr14, D14S16), ILSTS012 (U16, Chr11, D11S26), ILSTS015 (U07, Chr25, D25S3), ILSTS016 (U04, Chr21, D21S22), ILSTS017 (X, DXS11), ILSTS018 (U15, Chr06, D6S15), ILSTS019 (U07, Chr25, D25S7) and ILSTS020 (U05, Chr10, D10S27). These results contribute to the international effort to improve the bovine genetic map.  相似文献   

14.
Three new diterpenes koninginols A-C (13) and two new sesquiterpenoids 11-hydroxy-15-drimeneoic acid (4), koninginol D (5), together with twelve known compounds (617) were isolated from the endophytic fungus Trichoderma koningiopsis A729 derived from Morinda officinalis. Their structures were fully assigned with the aid of extensive spectroscopic analysis and reported data from the previous literatures. Koninginols A and B were disclosed as intriguing diterpene alkaloids, whereas the koninginol C was disclosed as one of the two examples of harziandione diterpene. All the isolates were evaluated for their antitumor activity, and compounds 12, 46, 1113, 1617 were evaluated for their antibacterial activity, wherein the new compounds 1 and 2 exhibited significant antibacterial activity against Bacillus subtilis with MIC values of 10 and 2 μg/mL, respectively.  相似文献   

15.
Four new diterpenes have been isolated from Sideritis serata: lagascol (4, ent-8,5-friedopimar-5-ene-15S,16-diol), tobarrol (8, ent-15-beyerene-12α,17-diol), benuol (12, ent-15-beyerene-7α,17-diol) and serradiol (18, ent-16R-atis-13-ene-16,17-diol). The previously known diterpenes lagascatriol (1, ent-8,5-friedopimar-5-ene-11β,15S,16-triol), jativatriol (2, ent-15-beyerene-1β,12α,17-triol), conchitriol (3, ent-15-beyerene-7α,12α,17-triol) and sideritol (17, ent-16R-atis-13-ene-1β,16,17-triol) have also been obtained from the same source.  相似文献   

16.
Long-term cultivation of human cells, including stem cells, can lead to essential transformations of the karyotype and genetic instability. The aim of this research was a comparative cytogenetic study of the karyotype of new human stem cell line 4BL at 160 and 205 passages. During a standard cytogenetic examination, the nullisomy and monosomy of chromosomes 10 and 13, monosomy of chromosomes 4, 8, 11, 15, 17, 21, and X; and t(1, 11), t (5, 15), t(12, 15), and t(16, 21) were observed; also, six regular marker chromosomes were detected. At 160 and 205 passages, the modal class of the karyotype was 42–43 chromosomes. While passaging increased frequency of polyploidy cells (from 2.8 to 36%), disappearance of nearhaploid cells (22.1% at the 160th passage) and a decreased level of early division of chromatids (from 5 to 1.5%) were observed. We assume the stabilization of the karyotype of cell line 4BL at 205 passages and consider that it is necessary to conduct an additional molecular and cytogenetic study for the objective identification of the number of chromosomes of the modal class, as well as the number of chromosomal anomalies, and for forecasting the direction of the karyotype evolution of human cells 4BL in vitro.  相似文献   

17.
Eight new cases of reciprocal translocation in the domestic pig are described. All the rearrangements were highlighted using GTG banding techniques. Chromosome painting experiments were also carried out to confirm the proposed hypotheses and to accurately locate the breakpoints. Three translocations, rcp(4;6)(q21;p14), rcp(2;6)(p17;q27) and rcp(5;17)(p12;q13) were found in boars siring small litters (8.3 and 7.4 piglets born alive per litter, on average, for translocations 2/6 and 5/17, respectively). The remaining five, rcp(5;8)(p12;q21), rcp(15;17)(q24;q21), rcp(7;8)(q24;p21), rcp(5;8)(p11;p23) and rcp(3;15)(q27;q13) were identified in young boars controlled before entering reproduction. A decrease in prolificacy of 22% was estimated for the 3/15 translocation after reproduction of the boar carrier. A parental origin by inheritance of the translocation was established for the (5;8)(p11;p23) translocation. The overall incidence of reciprocal translocations in the French pig populations over the 2000/2001 period was estimated (0.34%).  相似文献   

18.
[(11)C]Hemicholinium-15 ([(11)C]HC-15) and [(18)F]hemicholinium-15 ([(18)F]HC-15) have been synthesized as new potential PET tracers for the heart high-affinity choline uptake (HACU) system. [(11)C]HC-15 was prepared by N-[(11)C]methylation of the appropriate precursor, 4-methyl-2-phenyl-morpholin-2-ol, using [(11)C]CH(3)OTf in 55-70% radiochemical yield decay corrected to end of bombardment (EOB) and 2-3Ci/mumol specific activity at end of synthesis (EOS). [(18)F]HC-15 was prepared by N-[(18)F]fluoromethylation of the precursor using [(18)F]FCH(2)OTf in 20-30% radiochemical yield decay corrected to EOB and >1.0Ci/mumol specific activity at EOS. The biodistribution of both compounds was determined in rats at 20min post-intravenous injection, and the results show the heart region uptakes 1.32+/-0.75%ID/g in R-ventricle for [(11)C]HC-15 and 1.28+/-0.81%ID/g in L-ventricle for [(18)F]HC-15, respectively. The dynamic PET imaging studies of [(11)C]HC-15 in rats were acquired 60min post-intravenous injection of the tracer using the IndyPET-II scanner. For the blocking experiments, the rats were intravenously pretreated with 3.0mg/kg of unlabeled HC-15 prior to [(11)C]HC-15 injection. [(11)C]HC-15 rat heart PET studies show rapid heart uptake to give clear heart images. The rat heart PET blocking studies found no significant blocking effect. The dynamic PET studies in normal and ablated dogs were performed using Siemens PET scanner with [(13)N]NH(3), [(11)C]HC-15, and [(18)F]HC-15. PET studies in dogs of both [(11)C]HC-15 and [(18)F]HC-15 also show significant heart uptake and give images of the heart. However, there is no significant change in [(11)C]HC-15 L-ventricle uptake following radiofrequency ablation in the dog. These results suggest that the localization of HC-15 tracers in the heart is mediated by non-specific processes, and the visualization of HC-15 tracers on the heart is related to non-specific binding of HACU.  相似文献   

19.
Multiple endocrine neoplasia type 1 (MEN1) is an autosomal dominant disorder that predisposes affected individuals to neoplasms of the parathyroid glands, endocrine pancreas, anterior pituitary, and carcinoids. The MEN1 locus has been localized by family studies to 11q13, flanked by markers PGA and D11S97. Eight new polymorphisms located in three separate radiation-reduced somatic cell hybrid segregation groups were developed. The order of the new markers, within the context of previously described loci, was determined by linkage analysis on the Venezuelan reference pedigree. Four independent MEN1 families, consisting of 57 affected individuals, and 70 individuals at-risk for the disease were genotyped. Sixteen people inherited a chromosome that shows recombination between a linked marker and the disease. The nearest proximal and distal markers that show recombination with the disease are D11S822 and GSTP1, respectively, thereby narrowing the candidate region for MEN1 by 50% on the distal side. Using these loci in haplotype analysis, an accurate presymptomatic molecular diagnostic test has been developed. These new markers in 11q13 linked to MEN1 also facilitate the genetic and physical characterization of this very gene-rich region.  相似文献   

20.
Polyhydroxylated steroids from the soft coral Sinularia dissecta   总被引:1,自引:0,他引:1  
Jin P  Deng Z  Pei Y  Fu H  Li J  Van Ofwegen L  Proksch P  Lin W 《Steroids》2005,70(8):487-493
A repeated silica gel column chromatography followed by HPLC purification on the methanol extract of marine soft coral Sinularia dissecta, resulted in the isolation of fifteen polyhydroxylated steroids (1-15), involving six new C-18 functionalized steroids, 3beta-acetoxy-1alpha,11alpha-dihydroxygorgost-5-en-18-oic acid (1), gorgost-5-en-1alpha,3beta,11alpha,18-tetrol (2), 18-acetoxy-1alpha,3beta,11alpha-trihydroxygorgost-5-ene (3), 24(S)-3beta-acetoxy-1alpha, 11alpha-dihydroxyergost-5-en-18-oic acid (4), 24(S)-ergost-5-en-1alpha,3beta,11alpha,18-tetrol (5), and dissectolide (6). The structures of the new compounds were determined on the basis of extensive spectroscopic data (IR, MS, (1)H and (13)C NMR, HMQC, HMBC, and NOESY) analysis. Compound 6 was found as an unusual sterol bearing a lactone functionality.  相似文献   

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