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71.
The title ligand, N-(2-hydroxyphenyl)methyl-bis-(2-pyridylmethyl)amine, was prepared via a condensation-reduction synthetic route. The compounds, CuCl(C19H19N3O) and [CuBr(C19H19N3O)]+Br− · 3H2O, were readily synthesized from the reaction of CuCl or CuBr2 and the ligand in acetonitrile. The title copper(I) compound is an O-H ? Cl hydrogen-bonded linear chain of tetrahedrally coordinated copper centers, and the title copper(II) compound exists as two strongly tetragonally distorted dibromide bridged metal cations in a dimer with the phenol hydroxyl groups weakly bound in a trans-fashion to one of the bridging bromides. In the copper(I) complex the phenoxy group acts only as a hydrogen bond donor, whereas in the copper(II) complex it acts both as a ligand and a hydrogen bond donor. 相似文献
72.
Mandoli D. Olmstead R. Mishler B. D. Boore J. L. Smith A. R. Renzaglia K. Wolf P. Donoghue M. J. & O'Kelly C. J. 《Journal of phycology》2003,39(S1):37-37
We are funded to resolve the primary pattern of evolutionary diversification among green plants, and to establish a model for doing so that will be applicable to other groups of organisms with long evolutionary histories. To achieve this goal we will 1) complete a matrix of whole genome sequences for chloroplast and mitochondria and develop either nuclear or organellar bacterial artificial chromosome, BAC, libraries for about 50 representatives of the critical deep-branching lineages of green plants; 2) produce a comprehensive set of comparable morphological and ultrastructural data for these same taxa; 3) incorporate inferences from across the phylogenetic hierarchy in green plants using methods designed to permit scaling across studies. We shall indicate how this work will link to other research being conducted on green plants and various scales, especially the concatenation of our data sets with theirs. We will present the fuzzy nodes we have chosen to resolve and discuss our choices of taxa in this preliminary report. Funded by NSF's Tree of Life Program, 2002–2006, DEB #0228655 (lead institution), #228432, #0228679, #0228729, #0228660, #0228576. 相似文献
73.
Richard G. Olmstead Jennifer A. Sweere Kenneth H. Wolfe 《Plant molecular biology》1993,22(6):1191-1193
Corrections to the published sequence of the tobacco chloroplast genendhF are presented, including a 90 bpAlu I restriction enzyme fragment internal to the gene that was apparently missed during the original sequencing effort. A summary of the corrections to the published tobacco chloroplast DNA that have come to light since its original publication is included. 相似文献
74.
T. K. Wood K. L. Olmstead S. I. Guttman 《Evolution; international journal of organic evolution》1990,44(3):629-636
Water relations of host plants modify Enchenopa binotata life histories by mediating the termination of egg dormancy, thereby promoting synchronization of egg hatch. Dormant eggs must undergo dehydration and subsequent hydration to begin development. Dehydration of eggs is brought about in the field by declining water levels in branches during the fall and by prolonged cold. Hydration of eggs occurs when sap begins to rise in early spring. Since the ascent of sap occurs at different times in the six species of Enchenopa host plants, the phenology of egg hatch and adult maturation are allochronic. Shifts to novel host plants differing in phenology promote asynchrony of Enchenopa life histories among host-plant species. Thus, the host plant acts as an extrinsic disruptive factor that may promote genetic divergence and temporal reproductive isolation in Enchenopa. 相似文献
75.
TOSHIHIRO TOKIWA DAVID MODRÝ AKIRA ITO KATEŘINA POMAJBÍKOVÁ KLÁRA J. PETRŽELKOVÁ SOICHI IMAI 《The Journal of eukaryotic microbiology》2010,57(2):115-120
ABSTRACT. Troglocorys cava n. g., n. sp. is described from the feces of wild eastern chimpanzee, Pan troglodytes schweinfurthii, in Uganda. This new species has a spherical body with a frontal lobe, a long vestibulum, a cytoproct located at the posterior dorsal side of the body, an ovoid macronucleus, a contractile vacuole near the cytoproct, and a large concavity on the left surface of the body. Buccal ciliature is non‐retractable and consists of three ciliary zones: an adoral zone surrounding the vestibular opening, a dorso‐adoral zone extending transversely at the basis of the frontal lobe, and a vestibular zone longitudinally extending in a gently spiral curve to line the surface of the vestibulum. Two non‐retractable somatic ciliary zones comprise arches over the body surface: a short dorsal ciliary arch extending transversely at the basis of the frontal lobe and a wide C‐shaped left ciliary arch in the left concavity. Because of the presence of three ciliary zones in the non‐retractable buccal ciliature, the present genus might be a member of the family Blepharocorythidae, but the large left concavity and the C‐shaped left ciliary arch are unique, such structures have never been described from other blepharocorythids. 相似文献
76.
Synthesis,Characterization, and Antibacterial Activity of Structurally Complex 2‐Acylated 2,3,1‐Benzodiazaborines and Related Compounds 下载免费PDF全文
Divya Kanichar Lance Roppiyakuda Ewa Kosmowska Michelle A. Faust Kim P. Tran Felicia Chow Elena Buglo Michael P. Groziak Evan A. Sarina Marilyn M. Olmstead Isba Silva H. Howard Xu 《化学与生物多样性》2014,11(9):1381-1397
A set of 2‐acylated 2,3,1‐benzodiazaborines and some related boron heterocycles were synthesized, characterized, and tested for antibacterial activity against Escherichia coli and Mycobacterium smegmatis. By high‐field solution NMR, the heretofore unknown class of 2‐acyl‐1‐hydroxy‐2,3,1‐diazaborines has been found to be able to exist in several interconvertable structural forms along a continuum comprised of an open hydrazone a , a monomeric B‐hydroxy diazaborine b , and an anhydro dimer c . X‐Ray crystallography of one of the anhydro dimers, 17c , revealed it to have an unprecedented structure featuring a double intramolecular O→B chelation. The crystal structure of another compound, 37 , showed it to be based on a new pentacyclic B heterocycle framework. Nine compounds were found to possess activities against E. coli, and two others were active against M. smegmatis. The finding that these two contain isoniazid covalently embedded in their structures suggests that they might possibly be acting as prodrugs of this well‐known antituberculosis agent in vivo. 相似文献
77.
78.
Yao-Wu Yuan Chang Liu Hannah E. Marx Richard G. Olmstead 《Molecular phylogenetics and evolution》2010,54(1):23-35
The pentatricopeptide repeat (PPR) gene family, with hundreds of members in land plant genomes, has been recognized as a tremendous resource for plant phylogenetic studies based on publicly available genomic data from model organisms. However, whether this appealing nuclear gene marker system can be readily applied to non-model organisms remains questionable, particularly given the potential uncertainties in designing specific primers to only amplify the locus of interest from the sea of PPR genes. Here we demonstrate empirically the use of PPR genes in the family Verbenaceae and the Verbena complex. We also lay out a general scheme to design locus-specific primers to amplify and sequence PPR genes in non-model organisms. Intergeneric relationships within the family Verbenaceae were fully resolved with strong support. Relationships among the closely related genera within the Verbena complex and among some species groups within each genus were also well resolved, but resolution among very closely related species was limited. Our results suggest that PPR genes can be readily employed in non-model organisms. They may be best used to resolve relationships in a spectrum from among distantly related genera to among not-so-closely related congeneric species, but may have limited use among very closely related species. 相似文献
79.
Polyploidy is a prominent process in plant evolution and adaptation, but molecular phylogenetic studies of polyploids based on DNA sequences have often been confounded by their complex gene and genome histories. We report here a retroposon insertion in the nuclear gene granule-bound starch synthase I (GBSSI or "waxy") that clearly reveals the ancient hybrid history of the medically important polyploid species belladonna (Atropa belladonna) and resolves the controversy over the taxonomic group to which it belongs, the tribe Hyoscyameae (Solanaceae). Our inferences based on the pattern of presence or absence of the retroposon insertion are corroborated by phylogenetic analyses of the GBSSI gene sequences. This case may suggest that retroposons are promising molecular markers to study polyploid evolution. 相似文献
80.