Vaucheriaxanthin is 19'-OH and not 19-OH neoxanthin. This structural conclusion was borne out by mass, PMR and infrared (IR) spectra from the free pigment and its derivatives (vaucheriaxanthal, vaucheriaxanthal-diacetate, vaucheriaxanthal-diacetate-mono (trimethylsilyl) -ether, vaucheriaxanthintriacetateand triacetate-monosilanate, vaucheriaxanthin-dimethylether) and by comparison of the charac...

1 Department of Neurosurgery, Johns Hopkins University, Baltimore, Maryland, United States of America, 2 Krieger Mind/Brain Institute, Johns Hopkins University, Baltimore, Maryland, United States of America, 3 Department of Neuroscience, Johns Hopkins University, Baltimore, Maryland, United States of America, 4 Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland,...

A new lobane-type diterpenoid, loba-8,10,13(15)-triene-14,17,18-triol 17-acetate (1), and 5 known compounds, lobatriene (2), (17 R)-loba-8,10,13(15)-triene-17,18-diol (3), 14,17-diacetate (4), 14-acetate (5), lobatrienetriol (6), were isolated from a population of Okinawan soft coral Lobophytum sp. The structures these compounds elucidated by spectroscopy, including nuclear magnetic resonance h...

The objective of this study was to determine the antimicrobial effect of a combination of potassium lactate and sodium diacetate (0, 1.8, 3, and 4.5%; PURASAL P Opti. Form 4, 60% solution) on the survival and growth of Listeria monocytogenes Scott A in pH-adjusted broth (5.5, 6.0, 6.5, and 7.0) stored at 4, 10, 17, 24, 30, and 37 degrees C. Appropriate dilutions of broth were enumerated by spir...

BACKGROUND Platelet dysfunction is a well-established disturbance in haemodialysis (HD) patients. Propyl gallate is a synthetic platelet activator with the property to stimulate platelet aggregation. The aim of the present study was to evaluate the influence of a single haemodialysis session on propyl gallate-induced platelet aggregation. METHODS Thirty-nine HD patients were enrolled in the s...

The conversion of readily available silylalkynes, iodobenzene diacetate, and azide anions was utilized to form and react cyanocarbenes. A copper(II)-catalyzed reaction was found to react in a different manner. Both of these methods benefit from the formation and in situ reaction of hypervalent iodonium alkynyl triflates in O-H insertion reactions.

In order to identify a substance by means of paper chromatography it is highly desirable to compare the running rates of as many of its derivatives as possible with the running rates of comparable derivatives of known substances. When only microgram quantities are available, the preparation of derivatives in good yield often presents a problem. It is the primary purpose of this communication to...