PubMed · 11629976
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F A Peeters. 1991. [Not Available].. https://pubmed.ncbi.nlm.nih.gov/11629976/
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The base-catalyzed reaction of carboxymethyl 3,4,6-tri-O-acetyl-alpha-D-glucopyranoside 2-O-lactone (prepared from isomaltulose) with amino acids and fatty amines under basic catalysis gave a series of new pseudoglucopeptides, nonionic amphiphiles, and polymerizable derivatives. The same reaction applied to alcohols provided the corresponding 2-(alpha-D-glucopyranosyloxy)acetyl esters with either basic or acidic catalysts.
Previous studies have classified a series of nonheme iron catalysts for olefin cis-dihydroxylation by H2O2 into two groups. Complex 1, [(TPA)Fe(OTf)2], representative of Class A catalysts, forms a low-spin FeIII-OOH intermediate that gives rise to a high-valent FeV(=O)OH oxidant. The preference of this catalyst for electron-rich olefins demonstrates its electrophilic character. On the other hand, complex 2, [(6-Me3-TPA)Fe(OTf)2], representative of Class B catalysts, prefers instead to oxidize electron-deficient olefins, suggesting an oxidant with nucleophilic character. It is suggested that such a nucleophilic oxidant may be the high-spin FeIII-OOH intermediate derived from 2 or the FeIV(=O)(*OH) species derived therefrom.
Acrylic bone cements prepared with activators of reduced toxicity have been formulated with the aim of improving the biocompatibility of the final material. The activators used were N,N-dimethylaminobenzyl alcohol (DMOH) and 4,4'-dimethylamino benzydrol (BZN). The toxicity, cytotoxicity, and antiseptic action of these activators were first studied. DMOH and BZN presented LD50 values 3-4 times higher than DMT, were less cytotoxic against polymorphonuclear leucocytes, and possessed an antimicrobial character, with a high activity against the most representative microorganisms involved in postoperative infections. The properties of the acrylic bone cements formulated with DMOH and BZN were evaluated to determine the influence of these activators on the curing process and the physicochemical characteristics of the cements. A decrease of the peak temperature was observed for the curing with DMOH or BZN with respect to that of one commercially available formulation (CMW 3). However, residual monomer content and mechanical properties in tension and compression were comparable to those of CMW 3. The biocompatibility of acrylic bone cements containing DMOH or BZN was studied and compared with CMW 3. To that end, intramuscular and intraosseous implantation procedures were carried out and the results were obtained from the histological analysis of the surrounding tissues at different periods of time. Implantation of rods of cement into the dorsal muscle of rats showed the presence of a membrane of connective tissue, which increased in collagen fibers with time of implantation, for all formulations. The intraosseous implantation of the cements in the dough state in the femur of rabbits, revealed a higher and early osseous neoformation, with the presence of osteoid material surrounding the rest of the cured material, for the cement prepared with the activator BZN in comparison with that obtained following the implantation of the cement cured with DMOH or DMT (CMW 3).