Chromatographic determination of the absolute configuration of an acyclic secondary alcohol using difluorodinitrobenzene

A chromatographic determination method was developed for the absolute configuration of an acyclic secondary alcohol using the characteristic functions of 1,5-difluoro-2,4-dinitrobenzene (FFDNB). This method relies on the formation of the fixed favorable conformation of a secondary alcohol-DLA (2,4-dinitrophenyl-5-leucinamide) derivative and its recognition by ODS silica gel. The secondary alcohol reacted first with FFDNB under mild basic conditions, and L-leucinamide or DL-leucinamide was then introduced into the secondary alcohol-FDNB derivative. Because the conformations of the resulting alcohol-DLA derivatives were rigidly fixed by the dinitrobenzene plane, the absolute configuration at the asymmetric carbon of the secondary alcohol tested can be definitely deduced by the elution behavior of both of the diastereomers in the HPLC and/or LC/MS. One of the diastereomers has the cis (Z)-type arrangement of two more hydrophobic substituents of the alcohol and leucinamide moieties, the more hydrophobic side chain and isobutyl groups, to the plane of the dinitrobenzene, whereas another diastereomer has the opposite arrangement (trans (E)-type). Therefore, the cis arrangement interacts more strongly with the ODS silica gel and has a longer retention time than that of the trans-type arrangement. This established method was successfully applied to various chiral acyclic secondary alcohols including chloramphenicol and 4-hydroxyphenyllactic acid. Finally, the limitations of this method were also examined.

Linear focal elastosis associated with striae distensae in an elderly woman.

We report the case of a 73-year-old woman with linear focal elastosis (LFE) associated with striae distensae. Yellow palpable striae were found extending horizontally in the lumbar region. The yellow striae appeared to be joined to striae distensae in the lateral sides of the yellow striae. Striae distensae were also present in regions other than the back but were not associated with yellow striae. Histologic examination of a yellow stria revealed a focal increase in elastic fibers in the dermis. Although there have been some unusual cases of LFE arising in women or in young persons, this disorder still predominantly affects aged men. A fairly uniform feature of LFE is its occurrence on the dorsal skin, suggesting involvement of this specific anatomical site in its pathogenesis. We suspect that LFE usually arises de novo in the skin, although striae distensae may also be a cause of it.

Alteration of fecal bacterial flora following oral administration of bifidobacterial preparation.

The fecal bacterial flora was examined in multiple stool specimens from 14 subjects with gastrointestinal disorders before, during and after the oral administration of bifidobacterial preparation (BBG, viable B. breve and B. bifidum, 3 X 10(9) or 6 X 10(9) per day) for 2 or 3 weeks. Enumerations of fecal bacterial flora showed no conspicuous alterations in total anaerobic bacterial counts during the BBG therapy, however the total number of bifidobacteria in feces increased significantly, and of E. coli and other aerobacteria showed a tendency to decline. The administered B. breve and B. bifidum were recovered in the feces at a concentration of 10(8)/g and of 10(7) to 10(8)/g, respectively. Both species continued to be excreted over 2 weeks after completion of the medication in the feces at concentrations of 10(6) to 10(7)/g and of 10(5) to 10(6)/g respectively, and diminished rapidly in 5 patients and continued at essentially the same level as during the medication in 6 patients. During the treatment the pH, urease activity and ammonia content in feces became lowered and showed a rerise after therapy. Symptomatic discomforts including abdominal distension and pain, anorexia, edema and fever of undetermined origin were reduced during the therapy. Urinalysis, hematological examinations and blood biochemical tests including blood ammonia level, however revealed no significant change.