Ehlers-Danlos syndrome (EDS) type VIIC is a newly recognized human disorder which results from failure to remove the amino-terminal propeptide of type I procollagen. Four cases of EDS type VIIC have been reported, and here we describe a fifth case. The propositus was a 1,445 g male infant born at 30 weeks of gestation following premature rupture of membranes. He had wide fontanelles, prominent eyes with swollen eyelids and blue sclerae, anteverted nostrils, micrognathia, umbilical hernia, short stubby fingers, and cutis laxa with hirsutism. At age 3 months, during the repair of the umbilical hernia, he was noted to have unusual skin fragility. Examination of skin by scanning electron microscopy showed frayed collagen fibrils, and transmission electron microscopy showed the hieroglyphic collagen fibril morphology characteristic of the disorder. As reported in other cases, cultured fibroblasts synthesized type I procollagen that was very poorly processed at the amino-terminal propeptide cleavage site. the 5 known cases of human EDS type VIIC characterize a distinct clinical phenotype, making this condition recognizable at birth before manifestation of severe skin fragility. The diagnosis can be confirmed by biochemical studies of type I procollagen synthesis and by electron microscopic examination of skin.

27-and 36-membered ring peptides were prepared using glycine, (2S, 3'S)4methyL2-(2'-oxo-3'-isobutyl-l '-piperaziny1)pentanoic acid (2) and (2 S,3' S)-3-pheny1-2-(2'-0~0-3'-benzyl-l '-pipera-ziny1)propanoic acid as the units of peptides. The interactions of 1-phenylethylammonium (1) and p-methoxy-I-phenylethylammonium bromides (11) with these cyclic peptides were studied by 'H and 13C NMR measurements in CDCI,. It was found from these results that the peptides distinguish the enantiomers (Rand S-isomers) of the substrates. Furthermore, it was shown that the enantioface-differentiating abilities of 36-membered ring peptides are superior to those of , 27-membered rings. 0 1990, HUthig & Wepf Verlag, Basel CCC 0025-1 16X/90/$03.00

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The important r81e of lipoic acid on the oxidation-reduction and acyl transfer reactions in biological systems is well known. A few synthetic lipoic polymers have been reported recently including aminoethylated Sephadex or aminoalkyl glass beads2) covalently bound with lipoic acid, and their reduced forms (thiols) have been evaluated as a polymeric reducing agent or an affinity adsorbant for lipoamide dehydrogenase.To clarify the redox and the catalytic behaviours of polymers bearing the 1 ,Zdithiolane structure in the matrix, we synthesized polyurethane by the reaction of 4,4-bis(hydroxymethy1)-1,Zdithiolane (2) with a diisocyanate(3) and characterized the reactivity of the resulting polymer (4) 2 was prepared by treating 2,2-bis(bromomethyl)-I ,3-propanediol (pentaerythritol dibromide) (1) with sodium polysulfide3! Prior to the polymer synthesis, the reaction of 2 with phenyl isocyanate (reflux in dioxane) was attempted, giving the expected 4,4-bis(anilinocarbonyloxymethyl)-1,2-dithiolane, mp 156-16OoC, in 70% yield with a correct elemental analysis and a corresponding IR absorption spectrum.A few examples of the reactions of 2 with equimolar amounts of diisocyanates were shown in Tab. 1. In the case of poly(methy1ene diisocyanate), the use of dibutyltin dilaurate (BTL) as catalyst and anisole as solvent gave the product with the highest viscosity; but the polymers produced were elastic masses hard to handle, and the polycondensation without solvent gave 40% 3597

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