5-Azacytidine,a new,highly effective cancerostatic

Zusammenfassung Die hohe bakteriostatische und cancerostatische Wirkung eines neuen Antimetaboliten, 5-Azacytidin, wird beschrieben.     

5-Methylangelicin: a new highly photosensitizing angular furocoumarin

5-Methylangelicin, a new highly photosensitizing angular furocoumarin, was studied in 2 different biological systems, the T2 phage and Ehrlich ascites tumor cells; in comparison with angelicin, the parent compound, it was several times more active.     

A new broad-spectrum anthelmintic: 2-(4-Thiazolyl)-5-isopropoxycarbonylamino-benzimidazole

Zusammenfassung Es werden die Synthese sowie die biologischen Eigenschaften des neuen Anthelminticums 2-(4-Thiazolyl)-5-isopropoxycarbonylaminobenzimidazols beschreiben.     

5-Methylangelicin: A new highly photosensitizing angular furocoumarin

Summary 5-Methylangelicin, a new highly photosensitizing angular furocoumarin, was studied in 2 different biological systems, the T₂ phage and Ehrlich ascites tumor cells; in comparison with angelicin, the parent compound, it was several times more active.Acknowledgments. The authors wish to thank Mrs M. Peron for her excellent technical assistance.     

Biological characterization of a new and highly potent synthetic analogue of corticotrophin

Zusammenfassung Ein ACTH-Analogon:d-Ser¹-Nle⁴-(Val-NH₂)²⁵--1-25-Corticotrophin wurde tierexperimentell sowie orientierend humanpharmakologisch untersucht. Das Pentacosapeptid (DW-75) zeigt auf Grund der Substitution von 3 Aminosäuren eine gegenüber Peptiden mit natürlicher Sequenz beachtlich erhöhte ACTH-Aktivität.     

Triosephosphate isomerase: a highly evolved biocatalyst

Triosephosphate isomerase (TIM) is a perfectly evolved enzyme which very fast interconverts dihydroxyacetone phosphate and d-glyceraldehyde-3-phosphate. Its catalytic site is at the dimer interface, but the four catalytic residues, Asn11, Lys13, His95 and Glu167, are from the same subunit. Glu167 is the catalytic base. An important feature of the TIM active site is the concerted closure of loop-6 and loop-7 on ligand binding, shielding the catalytic site from bulk solvent. The buried active site stabilises the enediolate intermediate. The catalytic residue Glu167 is at the beginning of loop-6. On closure of loop-6, the Glu167 carboxylate moiety moves approximately 2 Å to the substrate. The dynamic properties of the Glu167 side chain in the enzyme substrate complex are a key feature of the proton shuttling mechanism. Two proton shuttling mechanisms, the classical and the criss-cross mechanism, are responsible for the interconversion of the substrates of this enolising enzyme.     

Synthesis and properties of praziquantel,a novel broad spectrum anthelmintic with excellent activity against Schistosomes and Cestodes

Summary Synthesis and properties of 2-cyclohexylcarbonyl-1,3,4,6,7,11b-hexahydro-2H-pyrazino [2,1-a] isoquinolin-4-one, a novel anthelmintic with excellent activity against all species of Schistosomes pathogenic to man and a wide range of cestodes, will be reported.     

A new compound effective against acute fascioliasis in sheep

Zusammenfassung 2-Acetoxy-4-chlor-3,5-dijodbenzanilid zeigte eine hohe Wirksamkeit gegen junge und gereifteF. hepatica andH. controtus in Schaften bei einer oralen Dosis von 25 und 40 mg/kg. Die gute Verträglichkeit der Verbindung in Schafen ergab sich aus Feldversuchen in Australien.     

Synthesis of O1.5-(beta-D-galactopyranosyl) [DMet2, Hyp5] enkephalin amide, a new highly potent analgesic enkephalin-related glycosyl peptide

A new series of O-glycosyl enkephalins has been prepared, following a convergent strategy, with high chemical yields. The galactosyl analogue, O1.5-(beta-D-galactopyranosyl) [DMet2, Hyp5] enkephalin amide proved to be one of the most potent in vivo opioid agonists synthesized up to now.     

Reticulol,a new metabolic isocoumarin

Zusammenfassung Die Struktur des ausStreptomyces rubreticulae isolierten neuen Isocumarins, Reticulol, ist als 3-Methyl-6,8-dihydroxy-7-methoxyisocumarin ermittelt worden.     

Baluchistine,a new bisbenzylisoquinoline alkaloid

Summary The new phenolic bisbenzylisoquinoline alkaloid (+)-baluchistine, found inBerberis baluchistanica Ahrendt (Berberidaceae), has been assigned structure1. O-Methylation using ethereal diazomethane yields (+)-obaberine (2). Baluchistine is the 1 alkaloid of the oxyacanthine-berbamine group to incroporate a free phenolic function at C-6.this project was supported by NIH research grant CA-11450, awarded by the National Cancer Institute, PHS/DHEW.     

Reductionism,emergence, and effective field theories

In recent years, a “change in attitude” in particle physics has led to our understanding current quantum field theories as effective field theories (EFTs). The present paper is concerned with the significance of this EFT approach, especially from the viewpoint of the debate on reductionism in science. In particular, I shall show how EFTs provide a new and interesting case study in current philosophical discussion on reduction, emergence, and inter-level relationships in general.