ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

No abstract

Peptide-based vaccines consist of short antigen fragments derived from a specific pathogen. Alone, these peptide fragments are poorly or non-immunogenic; however, when incorporated into a proper delivery system, they can trigger strong immune responses. To eliminate the need for toxic and often ineffective oral adjuvants, we designed single molecule-based self-adjuvating vaccines against hookworms using natural and unnatural hydrophobic amino acids. Two vaccine conjugates were synthesized, consisting of B-cell epitope p3, derived from the hookworm Na-APR-1 protein; universal T-helper peptide P25; and either double copies of unnatural lipoamino acid (2-amino-D,L-eicosanoic acid), or ten copies of the natural amino acid leucine. After challenge with the model hookworm, Nippostrongylus brasiliensis, mice orally immunized with the conjugates, but without adjuvant, generated antibody responses against the hookworm epitope, resulting in significantly reduced worm and egg burdens compared to control mice. We have demonstrated that vaccine nanoparticles composed exclusively of natural amino acids can be effective even when administered orally.

Terpenes Terpenes U 0200 O-N Intramolecular Acyl Migration Strategy in Water-Soluble Prodrugs ofTaxoids. -The highly water-soluble canadensol prodrug (III) is synthesized and its conversion to its parent drug canadensol (IV) via O-N acyl migration under physiological conditions is observed. During the conversion into (IV), no additional functional auxiliaries are released. The studies on water-soluble prodrugs with regard to paclitaxel and canadensol suggest that this strategy can be applied to other 3'-N-acyltaxoids with similar results. However, further application of the prodrug strategy to docetaxel is abandoned, due to hydrolysis of the Boc group under physiological conditions. -(SKWARCZYNSKI, M.; SOHMA, Y.; KIMURA, M.; HAYASHI, Y.; KIMURA, T.; KISO*, Y.; Bioorg. Med. Chem. Lett. 13 (2003) 24, 4441-4444; Dep. Med. Chem., Kyoto Pharm. Univ., Yamashina, Kyoto 607, Japan; Eng.) -H. Hoennerscheid 13-145

Ring closure reactions Ring closure reactions O 0130Mercuric Triflate Catalyzed Hydroxylative Carbocyclization of 1,6-Enynes. -The novel title process involves mercuration of a terminal alkyne, carbocyclization, hydration, and photodemercuration sequence regenerating the catalyst. No clean reaction course is observed when the construction of six-or seven-membered rings is attempted. The mercuric triflate-tetramethylurea complex can be equally used for the acid-sensitive substrates. -(NISHIZAWA*, M.; YADAV, V. K.; SKWARCZYNSKI, M.; TAKAO, H.; IMAGAWA, H.; SUGIHARA, T.; Org. Lett. 5 (2003) 10, 1609-1611; Fac. Pharm. Sci., Tokushima Bunri Univ., Yamashiro, Tokushima 770, Japan; Eng.) -Steudel 36-037 2003 Ring closure reactions