Unusual orientation and reactivity of alkyl halides in water-soluble cavitands

2014 ◽  
Vol 5 (11) ◽  
pp. 4382-4387 ◽  
Author(s):  
Richard J. Hooley ◽  
Jesse V. Gavette ◽  
Magi Mettry ◽  
Dariush Ajami ◽  
Julius Rebek
Keyword(s):  
Alkyl Halides ◽  
Water Soluble

Binding of alkyl halides in water-soluble cavitands with urea rims

2018 ◽  
Vol 42 (12) ◽  
pp. 9945-9948 ◽  
Author(s):  
Yang Yu ◽  
Yong-Sheng Li ◽  
Julius Rebek
Keyword(s):  
Alkyl Halide ◽  
Alkyl Halides ◽  
Water Soluble

Alkyl halide guests in cavitands move rapidly and maintain halide to contact with the aryl surfaces of the host.

Theoretical investigation on the binding of alkyl halides and cyclohexyl halides in water-soluble cavitands

2019 ◽  
Vol 728 ◽  
pp. 174-180
Author(s):  
Ioannis D. Petsalakis ◽  
Demeter Tzeli ◽  
Giannoula Theodorakopoulos ◽  
Julius Rebek
Keyword(s):  
Theoretical Investigation ◽  
Alkyl Halides ◽  
Water Soluble

Alkaloids of the Australian Rutaceae: Lunasia quercifolia. II. The Nature of Lunasine

1959 ◽  
Vol 12 (3) ◽  
pp. 458 ◽  
Author(s):  
JR Price
Keyword(s):  
Oxygen Atom ◽  
Methyl Iodide ◽  
Principal Component ◽  
Alkyl Halides ◽  
Water Soluble ◽  
Methyl Group

The principal component of the mixture of water-soluble alkaloids of Lunasia quercifolia is shown to be the quaternary 4-methoxy-1-methylquinolinium structure IV corresponding to the 1-methyl-4-quinolone alkaloid lunacrine. The formation of IV from lunacrine and methyl iodide involves addition of the methyl group to the quinolone oxygen atom. It is suggested that this, as with the γ-pyrones, is the usual mode of reaction of 4-quinolone with alkyl halides. The properties of 4-methoxyquinolinium salts are discussed in relation to the conversion of furoquinoline alkaloids to the iso-alkaloids.

A Resorcinol-Formaldehyde Resin as an Embedding Material for Electron Microscopy of Membranes

1969 ◽  
Vol 27 ◽  
pp. 328-329 ◽  
Author(s):  
J. G. Robertson ◽  
D. F. Parsons
Keyword(s):  
Electron Microscopy ◽  
Osmium Tetroxide ◽  
Neutral Lipids ◽  
Lipid Extraction ◽  
Water Soluble ◽  
Formaldehyde Resin ◽  
Electron Microscope Autoradiography ◽  
Resorcinol Formaldehyde ◽  
Major Disadvantage ◽  
Cell Organization

The extraction of lipids from tissues during fixation and embedding for electron microscopy is widely recognized as a source of possible artifact, especially at the membrane level of cell organization. Lipid extraction is also a major disadvantage in electron microscope autoradiography of radioactive lipids, as in studies of the uptake of radioactive fatty acids by intestinal slices. Retention of lipids by fixation with osmium tetroxide is generally limited to glycolipids, phospholipids and highly unsaturated neutral lipids. Saturated neutral lipids and sterols tend to be easily extracted by organic dehydrating reagents prior to embedding. Retention of the more saturated lipids in embedded tissue might be achieved by developing new cross-linking reagents, by the use of highly water soluble embedding materials or by working at very low temperatures.

Ferritin Labeled Antibody Staining of Thin Sections

1969 ◽  
Vol 27 ◽  
pp. 420-421
Author(s):  
J. D. McLean ◽  
S. J. Singer
Keyword(s):  
Biological Material ◽  
Water Soluble ◽  
Thin Sections ◽  
Antibody Staining ◽  
Thin Sectioning ◽  
Ultrathin Sections

The successful application of ferritin labeled antibodies (F-A) to ultrathin sections of biological material has been hampered by two main difficulties. Firstly the normally used procedures for the preparation of material for thin sectioning often result in a loss of antigenicity. Secondly the polymers employed for embedding may non-specifically absorb the F-A. Our earlier use of cross-linked polyampholytes as embedding media partially overcame these problems. However the water-soluble monomers used for this method still extract many lipids from the material.

The Effect of Benzene on Bluegill Olfactory Lamellae

1985 ◽  
Vol 43 ◽  
pp. 574-575
Author(s):  
D.R. Mattie ◽  
J.W. Fisher
Keyword(s):  
Surface Morphology ◽  
Soluble Fraction ◽  
Lepomis Macrochirus ◽  
Sublethal Concentration ◽  
Water Soluble ◽  
Major Constituent ◽  
Jet Fuels ◽  
Aquatic Biota ◽  
Normal Surface ◽  
Cacodylate Buffer

Jet fuels such as JP-4 can be introduced into the environment and come in contact with aquatic biota in several ways. Studies in this laboratory have demonstrated JP-4 toxicity to fish. Benzene is the major constituent of the water soluble fraction of JP-4. The normal surface morphology of bluegill olfactory lamellae was examined in conjunction with electrophysiology experiments. There was no information regarding the ultrastructural and physiological responses of the olfactory epithelium of bluegills to acute benzene exposure.The purpose of this investigation was to determine the effects of benzene on the surface morphology of the nasal rosettes of the bluegill sunfish (Lepomis macrochirus). Bluegills were exposed to a sublethal concentration of 7.7±0.2ppm (+S.E.M.) benzene for five, ten or fourteen days. Nasal rosettes were fixed in 2.5% glutaraldehyde and 2.0% paraformaldehyde in 0.1M cacodylate buffer (pH 7.4) containing 1.25mM calcium chloride. Specimens were processed for scanning electron microscopy.

An SEM study of raphide crystal initials in the leaves of vitis (grape)

1995 ◽  
Vol 53 ◽  
pp. 984-985
Author(s):  
H. J. Arnott ◽  
M. A. Webb ◽  
L. E. Lopez
Keyword(s):  
Calcium Oxalate ◽  
Water Soluble ◽  
Calcium Oxalate Crystals ◽  
Calcium Oxalate Crystal ◽  
Oxalate Crystals ◽  
Large Numbers ◽  
Sem Study ◽  
The Matrix ◽  
Crystal Cells ◽  
Crystal Idioblast

Many papers have been published on the structure of calcium oxalate crystals in plants, however, few deal with the early development of crystals. Large numbers of idioblastic calcium oxalate crystal cells are found in the leaves of Vitis mustangensis, V. labrusca and V. vulpina. A crystal idioblast, or raphide cell, will produce 150-300 needle-like calcium oxalate crystals within a central vacuole. Each raphide crystal is autonomous, having been produced in a separate membrane-defined crystal chamber; the idioblast''s crystal complement is collectively embedded in a water soluble glycoprotein matrix which fills the vacuole. The crystals are twins, each having a pointed and a bidentate end (Fig 1); when mature they are about 0.5-1.2 μn in diameter and 30-70 μm in length. Crystal bundles, i.e., crystals and their matrix, can be isolated from leaves using 100% ETOH. If the bundles are treated with H2O the matrix surrounding the crystals rapidly disperses.

Characterization of Chemical Impurities in Glutaraldehyde

1975 ◽  
Vol 33 ◽  
pp. 620-621
Author(s):  
B. J. Grenon ◽  
A. J. Tousimis
Keyword(s):  
Glutaric Acid ◽  
Spectroscopic Analysis ◽  
Aldol Condensation ◽  
Condensation Product ◽  
Amorphous Solid ◽  
Water Soluble ◽  
Impurity Component ◽  
Chemical Impurities ◽  
Soluble Liquid

Ever since the introduction of glutaraldehyde as a fixative in electron microscopy of biological specimens, the identification of impurities and consequently their effects on biologic ultrastructure have been under investigation. Several reports postulate that the impurities of glutaraldehyde, used as a fixative, are glutaric acid, glutaraldehyde polymer, acrolein and glutaraldoxime.Analysis of commercially available biological or technical grade glutaraldehyde revealed two major impurity components, none of which has been reported. The first compound is a colorless, water-soluble liquid with a boiling point of 42°C at 16 mm. Utilizing Nuclear Magnetic Resonance (NMR) spectroscopic analysis, this compound has been identified to be — dihydro-2-ethoxy 2H-pyran. This impurity component of the glutaraldehyde biological or technical grades has an UV absorption peak at 235nm. The second compound is a white amorphous solid which is insoluble in water and has a melting point of 80-82°C. Initial chemical analysis indicates that this compound is an aldol condensation product(s) of glutaraldehyde.

Water-soluble amphiphilic ruthenium(ii) polypyridyl complexes as potential light-activated therapeutic agents

2020 ◽  
Vol 56 (65) ◽  
pp. 9332-9335
Author(s):  
Sandra Estalayo-Adrián ◽  
Salvador Blasco ◽  
Sandra A. Bright ◽  
Gavin J. McManus ◽  
Guillermo Orellana ◽  
...  
Keyword(s):  
Cervical Cancer ◽  
Cancer Cells ◽  
Cellular Uptake ◽  
Therapeutic Agents ◽  
Water Soluble ◽  
Polypyridyl Complexes ◽  
Cervical Cancer Cells

Two new water-soluble amphiphilic Ru(ii) polypyridyl complexes were synthesised and their photophysical and photobiological properties evaluated; both complexes showed a rapid cellular uptake and phototoxicity against HeLa cervical cancer cells.

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