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The Raman spectra of gaseous formic acid ‐h2 and ‐d2 at 21 °C and higher temperatures have been recorded from about 70 to 4000 cm−1. The isotope ratios of the frequencies of the intermonomer vibrations, which deform the hydrogen bonds, have allowed a convincing assignment of these vibrations. All but one of the nine low‐frequency infrared and Raman bands of (HCOOH)2, and all seven of (DCOOD)2, have been assigned. It has been thought for 40 years that the symmetric hydrogen‐bond stretching vibration is the cause of a strong Raman band of (HCOOH)2 near 230 cm−1, but the new evidence shows clearly that this is the one low‐frequency fundamental that scatters too weakly to be detected. The spectra show bands at 1381 and 1307 cm−1 due to monomeric HCOOH which are assigned to ν4 and 2ν8, respectively, as the only feasible assignment. The Raman frequencies of the intramonomer modes of the dimer show that the intermonomer coupling is large for some modes and small for others. The Raman‐active hydrogen‐bonded O–H and O–D stretching modes, which are subject to a double‐minimum potential, scatter very weakly; they could not be distinguished from possible overtone and combination bands in Fermi resonance with the C–H or C–D stretching modes.

Aromatic sulfinyl chlorides have been prepared in high yield by direct chlorosulfination of some aromatic ethers (1,3-dimethoxybenzene, 2- methyl- and 4-chloro-1,3-dimethoxybenzene, 1,2,3-trimethoxybenzene, 1- and 2-methoxynaphthalene, 1,5-, 1,7-, 2,6- and 2,7- dimethoxynaphthalene ) with thionyl chloride alone at or below room temperature. Under the same conditions, 1,4-dimethoxynaphthalene and 1,3-dimethoxy-5-methylbenzene yield chlorinated starting materials and sulfides. 1,3,5-Trimethoxybenzene yields chlorinated starting material, sulfide, and a chlorinated disulfide. Some other ethers (e.g. anisole, 1,2- and 1,4-dimethoxybenzene, 5-chloro-1,3-dimethoxybenzene) are unreactive under these conditions.

3-[(2,3-Cyclopenteno-1-pyridinium)-methyl]-7-[2-syn-methoximino-2-(2-aminothiazol-4-yl)-acetamido]-ceph-3-em-4-carboxylate (HR 810) is a new cephalosporin derivative with an extremely broad antimicrobial spectrum. It is active against all bacterial species of clinical relevance, including strains which are frequently resistant towards cephalosporins of the third generation.

A series of analogues relating to the NH2-terminal region of the fibrin alpha chain, i.e., Gly-Pro-Arg-Pro, were prepared by stepwise solid-phase synthesis, and their abilities to inhibit fibrin polymerization and to prolong thrombin-initiated clotting time were evaluated. Among the analogues systematically modified at different positions, replacement of the NH2-terminal three residues of Gly-Pro-Arg-Pro by either chlorambucil, p-nitrophenyl-L-alanine, or p-aminophenyl-L-alanine gave inactive compounds in the thrombin time assay, whereas similar substitution or extension of the COOH terminus produced the highly active analogues Gly-Pro-Arg-Phe(4-NH2), 22%; Gly-Pro-Arg-Pro-Phe(4-NO2), and Gly-Pro-Arg-Pro-Phe(4-NH2), 105%; relative to Gly-Pro-Arg-Pro = 100% in the fibrin polymerization inhibitory assay. As potential photoaffinity labeling probes, analogues containing a nitrophenylalanine residue in position 4 or 5 underwent photolysis under the experimental photoactivation conditions. As a potential alkylating probe, Chl-Pro-Arg-Pro was selectively effective in inhibiting thrombin amidolysis and fibrin polymerization. In the latter assay, Chl-Pro-Arg-Pro was approximately 20 times more potent than Gly-Pro-Arg-Pro in inhibiting fibrin aggregation.

Die Losungskonformationen von Methadon (I), Isomethadon (II) sowie ihrer Hydro= Chloride und Methylammoniumjodide werden anhand von CD-Kurven und NMR- Spektren untersucht.

Die Acylierung von 1-substituierten Imidazolen (I) mit den Reagenzien (II) in 2-Stellung zu den Derivaten (III) gelingt in Gegenwart von Triathylamin und polaren Solventien; analog werden mit den Chlorarneisensaureestern (IV) die Ester (V) erhalten.

Laser photoionization spectra over the range 4.5–6.5 eV have been taken for iron clusters of from 2 to 25 atoms. From the observed ionization thresholds, the cluster ionization potentials are determined and trends in I.P. vs cluster size are examined. In the case of the iron dimer, a sharp, vertical threshold is seen which places the I.P. of Fe2 at 6.30±0.01 eV. Finally, SCF Xα scattered wave molecular orbital calculations have been carried out on the iron dimer and iron trimer. These results show the importance of ferromagnetic spin polarization in the electronic structure of Fe2 and Fe3.