Search PubMed⌕ Search

Biomedical subjects

R D Rogers

Publications and source records attributed to R D Rogers.

61 records · Page 4Linked to original sources

Platelet activating factor antagonist design. 2. X-ray structure of dimethyl 2,3,4,5-tetrahydro-5 beta-(3,4-methylenedioxyphenyl)-2-oxo-3 beta-(3,4,5-trimethoxybenzoyl)-3 alpha,4 alpha-furandicarboxylate.

C25H24O12, Mr = 516.46, triclinic, P-1, a = 8.780 (3), b = 11.298 (4), c = 13.271 (6) A, alpha = 71.77 (4), beta = 70.31 (3), gamma = 72.66 (3) degrees, V = 1189 A3, Z = 2, Dx = 1.44 g cm-3, lambda (Mo K alpha) = 0.71073 A, mu = 0.74 cm-1, F(000) = 540, T = 293 K, final R = 0.046 for 2495 observed [Fo greater than or equal to 5 sigma (Fo)] reflections. The observed structure reveals a trans disposition for the methoxycarbonyl and aryl substituents at positions 4 and 5 of the heterocycle and a cis-3,4-bis(methoxycarbonyl) relationship. There is no crystallographically imposed symmetry. Several intermolecular van der Waals interactions occur in the cell lattice of this compound.

Chemical Phenomena↗

Platelet activating factor antagonist design: structure of methyl trans-5-(3,4-dimethoxyphenyl)-2,3,4,5-tetrahydro-2-oxo-4- furancarboxylate.

C14H16O6, Mr = 280.28, monoclinic, P2(1)/c, a = 6.070 (2), b = 9.526 (5), c = 22.418 (5) A, beta = 94.32 (2) degrees, V = 1293 A3, Z = 4, Dx = 1.44 g cm-3, lambda(Mo K alpha) = 0.71073 A, mu = 0.71 cm-1, F(000) = 592, T = 293 K, final R = 0.043 for 1400 observed [F0 greater than or equal to 5 sigma(F0)] reflections. The observed structure confirms a trans stereorelationship for the two substituents and an envelope conformation for the lactone ring. There is no crystallographically imposed symmetry. An analysis of the closest contacts in the cell lattice reveals two types of intermolecular interactions for this compound.

Chemical Phenomena↗

Factors influencing consumers' selection of health insurance carriers.

The authors examine the factors and information influencing consumers' selection of health insurance carriers. The results indicate that consumers are sensitive to rising insurance premium costs. They perceive that the decision to select a carrier is critical, yet they are often unprepared (i.e., lack information) to make a judicious decision. Further, consumers are found to rely generally on personal experience rather than the traditional marketing media during the process of selecting insurers.

Advertising↗

Preparation, characterization, and antiviral activity of microbial metabolites of stemodin.

Screening studies for microbial transformation products of stemodin [2] have identified a number of microbial metabolites. Scale-up fermentation with Rhizopus arrhizus ATCC 11145 and Streptomyces sp. NRRL 5691 have resulted in the production of five metabolites that have been characterized with the use of 2D nmr and X-ray techniques. These metabolites have been identified as 18-hydroxystemodin [6], 16,18-dihydroxystemodin [7], 8 beta-hydroxystemodin [8], 8 beta, 18-dihydroxystemodin [9], and 7 beta, 8 beta-dihydroxystemodin [10]. The antiviral activity and cytotoxicity of the isolated metabolites have been evaluated.

Animals↗