Isolation and structures of the uprolides. I. Thirteen new cytotoxic cembranolides from the Caribbean gorgonian Euniceamammosa

1995 ◽  
Vol 73 (5) ◽  
pp. 643-654 ◽  
Author(s):  
Abimael D. Rodríguez ◽  
Ivette C. Piña ◽  
Javier J. Soto ◽  
Dalila R. Rojas ◽  
Charles L. Barnes
Keyword(s):  
Nuclear Magnetic Resonance Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Correlation Studies ◽  
Resonance Analysis ◽  
Eupalmerin Acetate ◽  
Chemical Correlation ◽  
The Caribbean ◽  
New Compounds

Thirteen new cembranolide diterpenoids, uprolides 3–15, have been isolated from the Caribbean gorgonian Euniceamammosa collected off the West coast of Puerto Rico. Several known metabolites, such as eupalmerin acetate (1) and eupalmerin (2), were also isolated from the same organism. The structures of the new compounds, which also showed modest in vitro cytotoxic activity, were assigned on the basis of extensive nuclear magnetic resonance analysis, chemical correlation studies, and by comparison with analogous spectral data from known cembranolide diterpenoids. One structure (3) was confirmed by X-ray diffraction analysis. Keywords: uprolides, Euniceamammosa, cytotoxicity, Caribbean, gorgonian.

Structure of nepetalic acid in the solid state and in solution by x-ray diffraction and nuclear magnetic resonance analysis

1981 ◽  
Vol 46 (16) ◽  
pp. 3302-3305 ◽  
Author(s):  
Edmund J. Eisenbraun ◽  
Clinton E. Browne ◽  
Ernest L. Eliel ◽  
David L. Harris ◽  
Asadur Rahman ◽  
...  
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Solid State ◽  
Magnetic Resonance ◽  
Nuclear Magnetic Resonance Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Resonance Analysis ◽  
Nuclear Magnetic

scholarly journals Crepidatumines C and D, Two New Indolizidine Alkaloids from Dendrobium crepidatum Lindl. ex Paxt.

Molecules ◽  
2019 ◽  
Vol 24 (17) ◽  
pp. 3071 ◽  
Author(s):  
Xiaolin Xu ◽  
Zesheng Li ◽  
Runmei Yang ◽  
Houguang Zhou ◽  
Yanbin Bai ◽  
...  
Keyword(s):  
Biosynthetic Pathways ◽  
X Ray Diffraction ◽  
Spectra Analysis ◽  
Indolizidine Alkaloids ◽  
X Ray ◽  
Planar Structures ◽  
The Absolute ◽  
New Compounds ◽  
Noesy Spectra

Two new indolizidine alkaloids, crepidatumines C (1) and D (2), together with crepidine (3), isocrepidamine (4), and crepidamine (5) were isolated from the Dendrobium crepidatum Lindl. ex Paxt. X-ray diffraction experiments established the absolute configurations of known compounds 3 and 4. The planar structures and relative configurations of new compounds 1 and 2 were elucidated by extensive spectra analysis including HR-ESI-MS, NMR (1H, 13C, 1H-1H COSY, HSQC, HMBC, and NOESY spectra), and the absolute configurations of 1 and 2 were suggested on the basis of possible biosynthetic pathways. The biological results confirmed that isocrepidamine (4) displayed a potent hypoglycemic effect in vitro without cytotoxicity.

Zirconyldichloride Modified Polycarbosilazane as Precursors for SiZrCNO Ceramics

2016 ◽  
Vol 697 ◽  
pp. 153-158
Author(s):  
Jia Jie Han ◽  
Dong Su ◽  
Yang Yu ◽  
Xue Ting Zhao ◽  
Xiao Jing Wang ◽  
...  
Keyword(s):  
Silicon Carbonitride ◽  
Nuclear Magnetic Resonance Analysis ◽  
X Ray Diffraction ◽  
Ceramic Yield ◽  
X Ray ◽  
Resonance Analysis ◽  
Argon Flow ◽  
Eds Analysis ◽  
Two Component ◽  
Stretching Vibration

Zirconyldichloride modified polycarbosilazane (PZrSZO) has been synthesized from two-component dichlorosilanes (methyldichlorosilane and methylvinyldichlorosilane), zirconyldichloride, and ethylenediamine using triethylamine as acid-absorbing agent and tetrahydrofuran as solvent. 1H nuclear magnetic resonance analysis of the as-synthesized PZrSZO suggest a structure of ethylene-bridged polycarbosilazane having –Si–N–C–C–N– as backbone chain with –CH=CH2, –H and –CH3 attached to Si as side groups, which is similar to that of non-modified PSZO precursor. Fourier transform infrared spectroscopy shows Zr–N stretching vibration peak appears at 532 cm-1 suggesting the incorporation of Zr into PSZO through aminolysis reaction between zirconyldichloride and ethylendiamine. SiZrCNO ceramic with the ceramic yield of 63 wt% is obtained through subsequent pyrolysis treatment at 1000 °C for 1 h under argon flow. EDS analysis shows its composition of SiZr0.01C1.03N0.25O0.84 with the Zr percentage of 1.45 wt%. X-ray diffraction analysis shows SiZrCNO ceramics are of mixed amorphous silicon carbonitride oxygen phase embraced with SiO2 nanocrystalline.

ChemInform Abstract: STRUCTURE OF NEPETALIC ACID IN THE SOLID STATE AND IN SOLUTION BY X-RAY DIFFRACTION AND NUCLEAR MAGNETIC RESONANCE ANALYSIS

1981 ◽  
Vol 12 (50) ◽  
Author(s):  
E. J. EISENBRAUN ◽  
C. E. BROWNE ◽  
E. L. ELIEL ◽  
D. L. HARRIS ◽  
A. RAHMAN ◽  
...  
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Solid State ◽  
Magnetic Resonance ◽  
Nuclear Magnetic Resonance Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Resonance Analysis ◽  
Abstract Structure ◽  
Nuclear Magnetic

A study on using expanded perlite with hydroxyapatite: Reinforced bio-composites

2021 ◽  
pp. 095441192199656
Author(s):  
Erdoğan Karip ◽  
Mehtap Muratoğlu
Keyword(s):  
Body Fluid ◽  
Xrd Analysis ◽  
Cold Isostatic Pressing ◽  
Expanded Perlite ◽  
X Ray Diffraction ◽  
Pressing Method ◽  
X Ray ◽  
Infra Red ◽  
Ft Ir

People are exposed to different kinds of diseases or various accidents in life. Hydroxyapatite (HA) has been widely employed for bone treatment applications. In this study, HA was extracted from sheep bones. Bio-composites were doped with 1, 5, and 10 wt.% of expanded perlite and 5 wt.% of ZrO2–MgO-P2O5. The bio-composites were prepared by the cold isostatic pressing method (250 MPa) and sintered at 900°C for 1 h. In order to evaluate the characteristics of the bio-composites, microhardness, density, X-ray diffraction (XRD), Fourier transform infra-red spectroscopy (FT-IR), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS) analyses were carried out on them. Additionally, the specimens whose characteristics were determined were kept in synthetic body fluid (SBF), and their in vitro behavior was examined. As a result, it was observed that microhardness increased as both the weight and the grain size of the expanded perlite were increased. Calcium silicate, tri-calcium phosphate, and hydroxyapatite were observed in the XRD analysis of all samples, and the formation of apatite structures was increased by addition of ZrO2–MgO–P2O5.

Fabrication and evaluation of calcium phosphate cement scaffold with controlled internal channel architecture and complex shape

2007 ◽  
Vol 221 (8) ◽  
pp. 951-958 ◽  
Author(s):  
X Li ◽  
D Li ◽  
B Lu ◽  
L Wang ◽  
Z Wang
Keyword(s):  
Tissue Engineering ◽  
Calcium Phosphate ◽  
Calcium Phosphate Cement ◽  
Complex Shape ◽  
X Ray Diffraction ◽  
X Ray ◽  
Precise Control ◽  
Internal Channel ◽  
Channel Architecture

The ability to have precise control over internal channel architecture, porosity, and external shape is essential for tissue engineering. The feasibility of using indirect stereo-lithography (SL) to produce scaffolds from calcium phosphate cement materials for bone tissue engineering has been investigated. The internal channel architecture of the scaffolds was created by removal of the negative resin moulds made with SL. Scanning electron microscopy (SEM) showed highly open, well-interconnected channel architecture. The X-ray diffraction examination revealed that the hydroxyapatite phase formed at room temperature in the cement was basically stable up to 850 °C. There was no phase decomposition of hydroxyapatite, although the crystallinity and grain size were different. The ability of resulting structure to support osteoblastic cells culture was tested in vitro. Cells were evenly distributed on exterior surfaces and grew into the internal channels of scaffolds. To exploit the ability of this technique, anatomically shaped femoral supracondylar scaffolds with 300-800 μm interconnected channels were produced and characterized.

A Novel Missense Mutation (p.P52R) in Amelogenin Gene Causing X-linked Amelogenesis Imperfecta

2007 ◽  
Vol 86 (1) ◽  
pp. 69-72 ◽  
Author(s):  
M. Kida ◽  
Y. Sakiyama ◽  
A. Matsuda ◽  
S. Takabayashi ◽  
H. Ochi ◽  
...  
Keyword(s):  
Novel Mutation ◽  
Dental Enamel ◽  
Fluorescence Analysis ◽  
Hereditary Disease ◽  
Amelogenesis Imperfecta ◽  
X Ray Diffraction ◽  
Japanese Family ◽  
X Ray ◽  
Amelogenin Gene

Amelogenesis imperfecta (AI) is a hereditary disease with abnormal dental enamel formation. Here we report a Japanese family with X-linked AI transmitted over at least four generations. Mutation analysis revealed a novel mutation (p.P52R) in exon 5 of the amelogenin gene. The mutation was detected as heterozygous in affected females and as hemizygous in their affected father. The affected sisters exhibited vertical ridges on the enamel surfaces, whereas the affected father had thin, smooth, yellowish enamel with distinct widening of inter-dental spaces. To study the pathological cause underlying the disease in this family, we synthesized the mutant amelogenin p.P52R protein and evaluated it in vitro. Furthermore, we studied differences in the chemical composition between normal and affected teeth by x-ray diffraction analysis and x-ray fluorescence analysis. We believe that these results will greatly aid our understanding of the pathogenesis of X-linked AI.

THE STUDY ON GRANTING BIOACTIVITY OF Ti ALLOY BY SURFACE TREATMENT

2010 ◽  
Vol 17 (02) ◽  
pp. 153-157 ◽  
Author(s):  
N. R. HA ◽  
Z. X. YANG ◽  
G. C. KIM ◽  
K. H. HWANG ◽  
D. S. SEO ◽  
...  
Keyword(s):  
Surface Treatment ◽  
Body Fluid ◽  
Surface Effect ◽  
In Vitro Test ◽  
Ti Alloy ◽  
X Ray Diffraction ◽  
X Ray ◽  
Chemical Surface ◽  
Vitro Test

Titanium alloys are superior of biocompatibility, mechanical properties and chemical stability. The biocompatibility of Ti alloy is related to the surface effect between human tissue and implant. Therefore, the purpose of this study is to investigate the bioactivity of Ti alloy by alkali and acid chemical surface treatment; and the biocompatibility of Ti alloy was evaluated by in vitro test. Higher bone-bonding ability and bioactivity of the substrate were obtained by the formation of apatite layers on the Ti alloy in simulated body fluid. The microstructures of apatite layer were investigated by scanning electron microscope (SEM) and the formed phases were analyzed with X-ray diffraction (XRD).

Mesenchymal Stem Cell Response to Surface Altered Porous Ti

2015 ◽  
Vol 638 ◽  
pp. 67-72
Author(s):  
Ana Maria Salantiu ◽  
Florin Popa ◽  
Petru Pascuta ◽  
Olga Soritau ◽  
Noemi Dirzu ◽  
...  
Keyword(s):  
Stem Cell ◽  
X Ray Diffraction ◽  
X Ray ◽  
Chemically Modified ◽  
Porous Ti ◽  
Average Porosity ◽  
Ft Ir ◽  
Cell Testing ◽  
Scanning Electron

This work aims to investigate the influence of surface conditioning of porous Ti for enhancing its biological activity, as assessed by in vitro stem cell testing. Porous Ti samples with an average porosity of 32% were processed by Powder Metallurgy with dextrin as a space holder. The samples were subjected to H2O2 treatment to form an enhanced TiO2 film, followed by a heat treatment at 400°C and 600°C aiming to the crystallization of the as-formed amorphous titanium oxide. Samples characterization was performed by Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FT-IR) and X-Ray Diffraction (XRD). The treated surfaces revealed to be made of both anatase and rutile TiO2, with groove–shaped structure and cracks on the surface of the TiO2 film. The intrinsic biocompatibility of the chemically modified porous Ti surfaces was assessed in vitro. In our cell culture tests, stem cells were found to attach and proliferate better on the chemically treated Ti surfaces compared to the control untreated Ti surfaces.

Sign in / Sign up

Export Citation Format

Share Document