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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Extractives from six species of Lamiaceae

Davies-Coleman, Michael Trevor January 1988 (has links)
In continuation of the phytochemical studies of plants belonging to the Lamiaceae (formerly Labiatae) the acetone extractives of six Southern African species from this family have been examined. The genus Syncolostemon has not been investigated before and a new 6- substituted-5 ,6-dihydro-a-pyrone , synrotolide was isolated from S. rotundifolius. The structure of synrotolide was fully elucidated as 6fixii [3'R, 61S-(diacetyloxy)-4 1R, 5 1 8-(dihydroxy)-1~-hepteny~ -5,6-dihydro-2H-pyran- 2-one. Oleanolic acid is the major component of both~ rotundifolius and S. densifloris. The flavonol quercetin was isolated from S. densifloris as its 3, 3', 4' , 7 tetramethyl ether. A further 6-substituted-5,6-dihydro-a-pyrone, boronolide, was obtained from Tetradenia barberae. The structure of boronolide was known but the absolute stereochemistry was unassigned. Chemical degradation established the total structure of this compound as 6R- [1 'R, 2'R, 3's -(trisacetyloxy)heptyl] -5,6-dihydro-2H-pyran-2-one. The chemistry of naturally occuring 6-substituted-5,6-dihydro-apyrones has not as such been previously reviewed and a comprehensive review covering the literature up to June 1987 is presented here. Three known labdane diterpenoids nepetaefuran, hispanalone and dubiin were iso lated from Leonotis nepetaefolia, Ballota africana and L. ocymifolia var. ocymifolia (formerly~ dubia). Both~ nepetaefolia and L. dubia have been examined before. An X-ray analysis of saponified dubiin and a circular dichroism study of 6-deacetyldehydrodubiin and related compounds corroborated the structure of dubiin as 48, 5R, 6R, 8R, 9R, 10R-[6-acetoxy-15,16-epoxy-9-hydroxylabda-13 (16), 14-dien-19, 20- olactoneJ. The chemotaxonomic relationships of the genera Ballota and Leonotis are discussed.
2

Monarda pectinata, Nutt., and related chemical problems

Burt, Joseph Bell, January 1935 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1935. / Typescript. Includes abstract and vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
3

Study of naturally occurring ortho-quinonoid compounds isolated from the roots of Salvia miltiorrhiza bunge.

January 1990 (has links)
by Kuk-ying Chui. / Thesis (Ph.D.)--Chinese University of Hong Kong, 1990. / Bibliography: leaves 84-88. / Chapter I. --- Acknowledgements --- p.1 / Chapter II. --- List of Nomenclature --- p.2 / Chapter III. --- Abstract --- p.7 / Chapter IV. --- Introduction --- p.8 / Chapter V. --- Results and Discussion / Chapter A. --- Isolation and structure elucidation of new compounds --- p.18 / Chapter B. --- Total synthesis of natural compounds isolated from Danshen --- p.26 / Chapter 1. --- Total synthesis of miltirone (10) (a modified procedure) --- p.26 / Chapter 2. --- "Total synthesis of 1,2-didehydro-miltirone (33)" --- p.29 / Chapter 3. --- Total synthesis of 4-methylene-miltirone (77) --- p.30 / Chapter C. --- Modifications of the A ring of miltirone (10) --- p.32 / Chapter 1. --- "Synthesis of 3,4-dihydro-7- isopropyl-phenanthrene-1(2H),5,6-trione ( 96)" --- p.32 / Chapter 2. --- "Synthesis of l-methyl-3,4-dihydro-7-isopropyl-phenanthrene-5,6-dione (100)" --- p.33 / Chapter 3. --- "Synthesis of l,2,3,4-tetrahydro-7- isopropyl-phenanthrene-5,6-dione (103)" --- p.35 / Chapter D. --- Modifications of miltirone (10) aimed at increasing its solubility in water --- p.36 / Chapter 1. --- "Synthesis of 1,2,3,4-tetrahydro-l-hydroxy-1 -methyl-7-isopropyl-phenanthrene-5,6-dione (106)" --- p.36 / Chapter 2. --- "Synthesis of 1,2,3,4-tetrahydro-trans-1 ,2-dihydroxy-1 -methy1-7-isopropyl-phenanthrene-5,6-dione (110)" --- p.38 / Chapter 3. --- "Synthesis of 1,2,3,4-tetrahydro-cis-1,2-dihydroxy-1 -methy1-7-isopropyl-phenanthrene-5,6-dione (114) and 1,2,3,4-tetrahydro-1-methy1-2-hydroxy-7-isopropyl-phenanthrene-5,6-dione (115)" --- p.41 / Chapter E. --- Modification of the A and B rings of miltirone (10) --- p.45 / Chapter VI. --- Conclusion --- p.47 / Chapter VII. --- Experimental Section --- p.50 / Chapter VIII. --- References --- p.84 / Chapter IX. --- Spectra --- p.89
4

Systematics and biology of Hemigenia R.Br. and Microcorys R.Br. (Lamiaceae).

Guerin, Gregory January 2008 (has links)
Title page, contents and abstract only. The complete thesis in print form is available from the University of Adelaide Library. / The genera Hemigenia R.Br. and Microcorys R.Br. (Lamiaceae, tribe Westringieae) have not been revised since 1870 and the existing taxonomy is inadequate. The current generic classification requires re-evaluation in light of more detailed knowledge of comparative morphology. The generic status of the related genera Hemiandra R.Br. and Westringlia Sm. also needs to be tested, as these genera share morphological characters with Hemigenia and Microcorys. In this thesis a new classification is discussed, but further data are required before this can be finalised. In particular, multiple DNA markers need to be sequenced with a slightly larger sample of species. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1311480 / Thesis (Ph.D.) -- University of Adelaide, School of Earth and Environmental Sciences, 2008
5

Systematics and biology of Hemigenia R.Br. and Microcorys R.Br. (Lamiaceae).

Guerin, Gregory January 2008 (has links)
Title page, contents and abstract only. The complete thesis in print form is available from the University of Adelaide Library. / The genera Hemigenia R.Br. and Microcorys R.Br. (Lamiaceae, tribe Westringieae) have not been revised since 1870 and the existing taxonomy is inadequate. The current generic classification requires re-evaluation in light of more detailed knowledge of comparative morphology. The generic status of the related genera Hemiandra R.Br. and Westringlia Sm. also needs to be tested, as these genera share morphological characters with Hemigenia and Microcorys. In this thesis a new classification is discussed, but further data are required before this can be finalised. In particular, multiple DNA markers need to be sequenced with a slightly larger sample of species. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1311480 / Thesis (Ph.D.) -- University of Adelaide, School of Earth and Environmental Sciences, 2008
6

Comparative study of the genus monarda

Albers, Carl Clarence, January 1936 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1936. / Typescript. Includes abstract and vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
7

Estudo Químico de Croton muscicapa Mull Arg. (Euphorbiaceae) e Avaliação da Composição Química Volátil de Ocimum spp (Lamiaceae) / Chemical study of Croton muscicapa Mull Arg. (Euphorbiaceae) and Evaluation of Volatile Chemical Composition of Ocimum spp (Lamiaceae)

Barreto, Milena Barbosa January 2008 (has links)
BARRETO, M. B. Estudo Químico de Croton muscicapa Mull Arg. (Euphorbiaceae) e Avaliação da Composição Química Volátil de Ocimum spp (Lamiaceae). 2008. 209 f. Dissertação (Mestrado em Química) - Centro de Ciências, Universidade Federal do Ceará, Fortaleza, 2008. / Submitted by Daniel Eduardo Alencar da Silva (dealencar.silva@gmail.com) on 2014-11-26T20:43:10Z No. of bitstreams: 1 2008_dis_mbbarreto.pdf: 9302589 bytes, checksum: c6f69fbce5c6aedebee941f669320dbb (MD5) / Approved for entry into archive by José Jairo Viana de Sousa(jairo@ufc.br) on 2014-12-22T16:42:50Z (GMT) No. of bitstreams: 1 2008_dis_mbbarreto.pdf: 9302589 bytes, checksum: c6f69fbce5c6aedebee941f669320dbb (MD5) / Made available in DSpace on 2014-12-22T16:42:51Z (GMT). No. of bitstreams: 1 2008_dis_mbbarreto.pdf: 9302589 bytes, checksum: c6f69fbce5c6aedebee941f669320dbb (MD5) Previous issue date: 2008 / This work describes the phytochemical studies of Croton muscicapa Müll. Arg. (Euphorbiaceae), commonly known as “velame de cheiro” and the volatile chemical composition of the aerial parts from Ocimum gratissimum and also Ocimum sp. The phytochemical studies of exsudate of the stems from C. muscicapa allowed the isolation and characterization of five substances: one triterpene: dammaradienol and four flavonoids: retusine, pachypodol, ombuine and 3,7,4´-trimethoxykaempferol. These substances are being reported for the first time for the species in study, while the dammaradienol and ombuine are being reported for the first time for the Euphorbiaceae family. All chemical substances have their structures elucidated through spectrometric techniques: IR, MS, 1D and 2D NMR (COSY, HSQC, HMBC), as well by comparison with literature data. The antioxidant potentials of the exsudate, hexanic and ethanol extracts of the leaves and stems were analyzed by using the DPPH radical scavenger. The volatile chemical composition of the essential oils of the leaves and inflorescences from Ocimum sp and O. gratissimum were examined by GC/MS and GC/FID. The inter and intraspecific variation of the chemical components present in the essential oils was avaluated pursuing the determination of the influence of extrernal factors such as seasonal harvesting (every month from march to december 2007), daylight time harvesting (6:00am, 10:00am, 2:00pm, 6:00pm), cultivation form of Ocimum sp species (garden beds exposed to the sun light and in greenhouses) and plant part (leaves and/or inflorescences). / Este trabalho descreve o estudo fitoquímico de Croton muscicapa Müll. Arg. (Euphorbiaceae) conhecido popularmente como “velame de cheiro”, bem como o estudo da composição química volátil das partes aéreas de Ocimum gratissimum e de Ocimum sp. A investigação fitoquímica realizada com o exsudato dos talos de C. muscicapa resultou no isolamento e caracterização de cinco substâncias, um triterpeno: damaradienol e quatro flavonóides: retusina, pachipodol, ombuina e 3,7,4’-trimetoxicanferol. Todos são relatados pela primeira vez para a espécie em estudo, enquanto que o damaradienol e a ombuina são relatados pela primeira na família Euphorbiaceae. A determinação estrutural das substâncias isoladas foi realizada através das técnicas espectrométricas: IV, EM e RMN uni e bidimensional (COSY, HSQC, HMBC) e comparação com os dados descritos na literatura. O potencial antioxidante do exsudato dos talos e dos extratos hexânicos e etanólicos das folhas e talos foi analisado utilizando o radical livre DPPH. A composição química volátil das folhas e inflorescências de Ocimum sp e de O. gratissimum foi determinada por CG-EM e CG-DIC. A variação inter e intra-específica dos constituintes químicos presentes nos óleos essenciais foi avaliada com o intuito de determinar a influência de alguns fatores externos como época de coleta (durante os meses de março a dezembro de 2007), horário de coleta durante o dia (6 h, 10 h, 14 h e 18 h), a forma de cultivo de espécimes de Ocimum sp (canteiros exposto ao sol e em estufas) e a parte da planta (folhas e/ou inflorescências).
8

Estudo QuÃmico de Croton muscicapa Mull Arg. (Euphorbiaceae) e AvaliaÃÃo da ComposiÃÃo QuÃmica VolÃtil de Ocimum spp (Lamiaceae) / Chemical study of Croton muscicapa Mull Arg. (Euphorbiaceae) and Evaluation of Volatile Chemical Composition of Ocimum spp (Lamiaceae)

Milena Barbosa Barreto 14 April 2008 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / Este trabalho descreve o estudo fitoquÃmico de Croton muscicapa MÃll. Arg. (Euphorbiaceae) conhecido popularmente como âvelame de cheiroâ, bem como o estudo da composiÃÃo quÃmica volÃtil das partes aÃreas de Ocimum gratissimum e de Ocimum sp. A investigaÃÃo fitoquÃmica realizada com o exsudato dos talos de C. muscicapa resultou no isolamento e caracterizaÃÃo de cinco substÃncias, um triterpeno: damaradienol e quatro flavonÃides: retusina, pachipodol, ombuina e 3,7,4â-trimetoxicanferol. Todos sÃo relatados pela primeira vez para a espÃcie em estudo, enquanto que o damaradienol e a ombuina sÃo relatados pela primeira na famÃlia Euphorbiaceae. A determinaÃÃo estrutural das substÃncias isoladas foi realizada atravÃs das tÃcnicas espectromÃtricas: IV, EM e RMN uni e bidimensional (COSY, HSQC, HMBC) e comparaÃÃo com os dados descritos na literatura. O potencial antioxidante do exsudato dos talos e dos extratos hexÃnicos e etanÃlicos das folhas e talos foi analisado utilizando o radical livre DPPH. A composiÃÃo quÃmica volÃtil das folhas e inflorescÃncias de Ocimum sp e de O. gratissimum foi determinada por CG-EM e CG-DIC. A variaÃÃo inter e intra-especÃfica dos constituintes quÃmicos presentes nos Ãleos essenciais foi avaliada com o intuito de determinar a influÃncia de alguns fatores externos como Ãpoca de coleta (durante os meses de marÃo a dezembro de 2007), horÃrio de coleta durante o dia (6 h, 10 h, 14 h e 18 h), a forma de cultivo de espÃcimes de Ocimum sp (canteiros exposto ao sol e em estufas) e a parte da planta (folhas e/ou inflorescÃncias). / This work describes the phytochemical studies of Croton muscicapa MÃll. Arg. (Euphorbiaceae), commonly known as âvelame de cheiroâ and the volatile chemical composition of the aerial parts from Ocimum gratissimum and also Ocimum sp. The phytochemical studies of exsudate of the stems from C. muscicapa allowed the isolation and characterization of five substances: one triterpene: dammaradienol and four flavonoids: retusine, pachypodol, ombuine and 3,7,4Â-trimethoxykaempferol. These substances are being reported for the first time for the species in study, while the dammaradienol and ombuine are being reported for the first time for the Euphorbiaceae family. All chemical substances have their structures elucidated through spectrometric techniques: IR, MS, 1D and 2D NMR (COSY, HSQC, HMBC), as well by comparison with literature data. The antioxidant potentials of the exsudate, hexanic and ethanol extracts of the leaves and stems were analyzed by using the DPPH radical scavenger. The volatile chemical composition of the essential oils of the leaves and inflorescences from Ocimum sp and O. gratissimum were examined by GC/MS and GC/FID. The inter and intraspecific variation of the chemical components present in the essential oils was avaluated pursuing the determination of the influence of extrernal factors such as seasonal harvesting (every month from march to december 2007), daylight time harvesting (6:00am, 10:00am, 2:00pm, 6:00pm), cultivation form of Ocimum sp species (garden beds exposed to the sun light and in greenhouses) and plant part (leaves and/or inflorescences).
9

The chemotaxonomy and biological activity of salvia stenophylla ( lamiaceae ) and related taxa

Gono-Bwalya, Angela 13 October 2003 (has links)
A dissertation submitted to the Faculty of Health Sciences, University of the Witwatersrand, in fulfilment of the requirements for the degree of Master of Medicine Johannesburg, South Africa, 2003 / Salvia stenophylla Burch, ex Benth. (Lamiaceae) is a perennial aromatic herb, which is widespread in the high altitude areas of the central and eastern parts of South Africa and also occurs in southwest Botswana and central Namibia. It is closely related to Salvia runcinata L. f. and Salvia repens Burch, ex Benth., with which it forms a species complex. The most recent revision of southern African Salvia species is that by Codd (1985). In this revision, the most important characters used in delimiting the three taxa were corolla size, calyx size and trichome density. As a result of intergrading morphological characters, the specific limits between the three taxa are not clear and positive identification of typical material is often difficult. Taxonomic delimitation through use of chemical characters was therefore the principle objective of this study. The taxa represented in this species complex are known in folk medicine and plant extracts have been used in the treatment of urticaria, body sores, and stomach ailments and as a disinfectant. S. stenophylla is reported to contain a-bisabolol, a compound that has anti-inflammatory properties. Based on the traditional uses of these plants and the international use of a-bisabolol to develop active cosmetic products, establishing a scientific rationale for the known uses was an important secondary objective / IT2018
10

Review on the effect of Salviae Miltiorrhizae Bunge (Danshen) in the management of coronary heart diseases /

Wong, Yat-wai, Patrick. January 2000 (has links)
Thesis (M. Med. Sc.)--University of Hong Kong, 2000. / Includes bibliographical references.

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