Cefcapene pivoxil-induced hypocarnitinemic hypoglycemia in elderly man with subclinical ACTH deficiency: a case report.

BACKGROUND: Drug-induced hypocarnitinemia has been noted as a cause of hypoglycemia in children. However, adult cases are extremely rare and pre-existing conditions (including endocrine disorders and frailty) have been suggested to be involved. Hypoglycemia due to drug-induced hypocarnitinemia is quite rare, and there were few reports of pivoxil-containing cephalosporin (PCC)-induced hypocarnitinemia in adults. CASE PRESENTATION: We present a case of an 87-year-old man with malnutrition, and frailty. He developed severe hypoglycemia with unconsciousness after taking cefcapene pivoxil hydrochloride, one of PCC, and hypocarnitinemia was diagnosed. Despite levocarnitine administration, asymptomatic mild hypoglycemia had persisted. Subsequent investigation revealed subclinical ACTH deficiency due to empty sella, which played a key role to maintain mild hypoglycemia as underlying disorder, and PCC-induced hypocarnitinemia triggered severe hypoglycemia. The patient responded to hydrocortisone therapy. CONCLUSIONS: We need to be aware of the facts that PCC can induce severe hypocarnitinemic hypoglycemia in elderly adults associated with frailty, malnutrition, and subclinical ACTH syndrome.

Synthesis of beta-analogues of C-mannosyltryptophan, a novel C-glycosylamino acid found in proteins.

alpha-C-Mannosyltryptophan (alpha-C-Man-Trp) has been found to be a novel post-translational modification of tryptophan found from some biologically important glycoproteins. In order to analyze the biological functions of alpha-C-Man-Trp, we have developed an efficient synthetic strategy for alpha-C-Man-Trp and its glucose and galactose analogues, starting from alpha-C-glycosidation of the corresponding hexapyranoside derivatives with tinacetylene. According to the synthetic routes, we describe here syntheses of beta-anomers of C-Man-Trp, and its glucose and galactose analogues from the corresponding beta-C-glycosylacetylenes. During this study, we have developed a highly stereocontrolled synthesis of beta-C-mannosylacetylene that is required for the synthesis of beta-C-Man-Trp, while the precedented method gave an anomeric mixture of the C-mannosylacetylene. The synthetic C-Man-Trp and its analogues were analyzed by HPLC.

Stereocontrolled syntheses of alpha-C-mannosyltryptophan and its analogues.

The total synthesis of alpha-C-mannosyltryptophan (C-Man-Trp), a naturally occurring C-glycosylamino acid, was achieved from a commercially available alpha-methyl-D-mannoside in 10 steps including the following key steps: the C-glycosidation of a mannose derivative with a stannylacetylene, Castro indole synthesis, and Sc(ClO4)3-promoted coupling with L-serine-derived aziridine carboxylate. The glucose- and galactose-analogues of C-Man-Trp were also synthesized in a similar manner. Conformational analyses of the synthesized C-glycosyltryptophan and its synthetic intermediate are briefly discussed.