RESUMO
Opium poppy (Papaver somniferum) is one of the world's oldest medicinal plants and a versatile model system to study secondary metabolism. However, our knowledge of its genetic diversity is limited, restricting utilization of the available germplasm for research and crop improvement. We used genotyping-by-sequencing to investigate the extent of genetic diversity and population structure in a collection of poppy germplasm consisting of 91 accessions originating in 30 countries of Europe, North Africa, America, and Asia. We identified five genetically distinct subpopulations using discriminate analysis of principal components and STRUCTURE analysis. Most accessions obtained from the same country were grouped together within subpopulations, likely a consequence of the restriction on movement of poppy germplasm. Alkaloid profiles of accessions were highly diverse, with morphine being dominant. Phylogenetic analysis identified genetic groups that were largely consistent with the subpopulations detected and that could be differentiated broadly based on traits such as number of branches and seed weight. These accessions and the associated genotypic data are valuable resources for further genetic diversity analysis, which could include definition of poppy core sets to facilitate genebank management and use of the diversity for genetic improvement of this valuable crop.
Assuntos
DNA de Plantas/genética , Genes de Plantas , Variação Genética , Genoma de Planta , Técnicas de Genotipagem , Papaver/genética , Polimorfismo de Nucleotídeo Único , Sementes/genética , Análise de Sequência de DNA , Alcaloides/metabolismo , Genótipo , Papaver/crescimento & desenvolvimento , Papaver/metabolismo , Fenótipo , Filogenia , Sementes/crescimento & desenvolvimento , Sementes/metabolismoRESUMO
Manganese(III) and manganese(II) complexes of halogenated sulfonamide tetraphenylbacteriochlorins were prepared for the first time via a transmetalation reaction and shown to be stable at room temperature. The behavior of the electronic states of the paramagnetic complexes is remarkably different from those of the metal-free bacteriochlorins or diamagnetic metallobacteriochlorins. The Mn3+ complex exhibits eight electronic transitions between different states from 300 to 1100 nm, with a very prominent band (molar absorption coefficient of ca. 50000 M-1 cm-1) at 829 nm. Ultrafast transient absorption showed the formation of an excited singquintet state that decays to a tripquintet state with a femtosecond lifetime. The tripquintet state decays in 5 ps, yielding a tripseptet state with a 570 ps lifetime. The electronic absorption of the Mn2+ complex more closely resembles those of diamagnetic metallobacteriochlorins, but the longest decay lifetime is only ca. 8 ps. The intense photoacoustic waves generated with near-infrared excitation suggest the use of these complexes in photoacoustic tomography.
Assuntos
Complexos de Coordenação/química , Manganês/química , Porfirinas/química , Teoria Quântica , Calorimetria , Complexos de Coordenação/síntese química , Estrutura Molecular , Processos Fotoquímicos , Fatores de TempoRESUMO
Progress in the photodynamic therapy (PDT) of cancer should benefit from a rationale to predict the most efficient of a series of photosensitizers that strongly absorb light in the phototherapeutic window (650-800â nm) and efficiently generate reactive oxygen species (ROS = singlet oxygen and oxygen-centered radicals). We show that the ratios between the triplet photosensitizer-O2 interaction rate constant (kD) and the photosensitizer decomposition rate constant (kd), kD/kd, determine the relative photodynamic activities of photosensitizers against various cancer cells. The same efficacy trend is observed in vivo with DBA/2 mice bearing S91 melanoma tumors. The PDT efficacy intimately depends on the dynamics of photosensitizer-oxygen interactions: charge transfer to molecular oxygen with generation of both singlet oxygen and superoxide ion (high kD) must be tempered by photostability (low kd). These properties depend on the oxidation potential of the photosensitizer and are suitably combined in a new fluorinated sulfonamide bacteriochlorin, motivated by the rationale.
Assuntos
Melanoma/tratamento farmacológico , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/uso terapêutico , Porfirinas/química , Porfirinas/uso terapêutico , Animais , Linhagem Celular Tumoral , Estabilidade de Medicamentos , Halogenação , Humanos , Camundongos , Camundongos Endogâmicos DBA , Fotoquimioterapia , Fotólise , Fármacos Fotossensibilizantes/farmacocinética , Porfirinas/farmacocinética , Oxigênio Singlete/químicaRESUMO
The development of large scale synthesis of enantiopure and thermally stable (R)- and (S)-BINOL molecules constitutes a key milestone in the field of asymmetric catalysis. Particularly, a great variety of chiral binaphthyl-based phosphorus compounds, herein represented by phosphite and phosphine classes, have earned considerable relevance due to their versatility as ligands in enantioselective metal-catalysed reactions, allowing the preparation of optically active products with the desired enantiopurity. This review highlights the most relevant concepts and accounts regarding general synthetic procedures for binaphthyl-based mono- and bidentate phosphites and phosphines. Furthermore, the search for environmentally benign chemical catalytic processes compelled us to also give special attention to the functionalisation of binaphthyl-based phosphorus ligands for use in alternative reaction media. When available, a critical selection of their applications in catalysis is briefly assessed.
Assuntos
Naftóis/química , Fosfinas/química , Fosfitos/química , Ligantes , Fosfinas/síntese química , Fosfitos/síntese químicaRESUMO
The title compound, C(25)H(24)O(4), a meth-oxy-methyl (MOM) bis-protected BINOL derivative containing a methyl substituent in position 3, is a key inter-mediate for the synthesis of a great variety of chiral auxiliaries. The planes of the naphthyl aromatic rings are at an angle of 70.74â (3)°. There are no conventional hydrogen bonds binding the mol-ecules.
RESUMO
Zinc and manganese complexes of porphyrin triads have been synthesized and are shown to be efficient as highly sensitive and selective tripod optical sensors for amines at the picomolar level.
Assuntos
Aminas/análise , Metaloporfirinas/química , Metaloporfirinas/síntese química , Dispositivos Ópticos , Técnicas de Química Sintética , Espectroscopia de Ressonância Magnética , Manganês/química , Modelos Moleculares , Estrutura Molecular , Espectrofotometria Ultravioleta , Zinco/químicaRESUMO
The inâ vitro phototoxicity of a photostable, synthetic, water-soluble, halogenated bacteriochlorin, 5,10,15,20-tetrakis(2-chloro-5-sulfophenyl)bacteriochlorin (TCPBSO3H), toward mouse melanoma (S91) cells is â¼60-fold higher than that of the analogous porphyrin, and is associated with very weak toxicity in the dark; 90% of S91 cells were killed in response to a light dose of 0.26â J cm(-2) in the presence of [TCPBSO3H]=5â µM. Inâ vivo toxicity toward DBA mice is very low, even at doses of 20â mg kg(-1). Inâ vivo pharmacokinetics and biodistribution of TCPBSO3H were studied in DBA mice with S91 tumors; 24â h after intraperitoneal injection of 10â mg kg(-1), TCPBSO3H demonstrated preferential accumulation in S91 mouse melanoma, with tumor-to-normal tissue ratios of 3 and 5 for muscle and skin, respectively. Photodynamic therapy (PDT) performed under these conditions, with 90â mW cm(-2) diode laser irradiation at λâ 750â nm for 20â min (total light dose of 108â J cm(-2)), resulted in tumor regression. Tumor recurrence was observed only approximately two months after treatment, confirming the efficacy of this PDT against melanoma.
Assuntos
Melanoma Experimental/tratamento farmacológico , Fármacos Fotossensibilizantes/química , Porfirinas/química , Animais , Linhagem Celular Tumoral , Halogenação , Injeções Intraperitoneais , Camundongos , Fotoquimioterapia , Fármacos Fotossensibilizantes/farmacocinética , Fármacos Fotossensibilizantes/uso terapêutico , Porfirinas/farmacocinética , Porfirinas/uso terapêutico , Espécies Reativas de Oxigênio/metabolismo , Fatores de Tempo , Distribuição TecidualRESUMO
The mol-ecules of the title compound, C(27)H(28)O(2), exhibit axial chirality. The planes of the aromatic rings of the tetra-lin ring systems make an angle of 85.72â (11)°. The non-aromatic rings adopt distorted half-chair conformations. In one of them, two C atoms of the four-atom aliphatic chain are disordered over two sites in a 0.75â (2):0.25â (2) ratio. The substituent phenyl ring is also disordered over two positions in a 0.59â (3):0.41â (3) ratio. There are no conventional hydrogen bonds joining the mol-ecules.