Abstract: A novel 2-piperidinecarboxylic acid derivative represented by the formula: ##STR1## wherein X represents an oxygen atom, a sulfur atom or a nitrogen atom to which a hydrogen atom is bound; and * represents that the configuration of the carbon atom binding to the carboxyl group is (S), (R) or a mixture of (S) and (R); and a pharmaceutically acceptable salt thereof which exerts an antitumor effect over a wide range of tumor cells.

Abstract: A novel megakaryocyte colony stimulating factor has been isolated from the supernatant of the culture obtained by cultivating a cell strain of a human large cell lung cancer. When the factor is applied to human or murine bone-marrow cells in vitro, it forms a megakaryocyte colony. Also, the factor increases the number of platelets in peripheral blood in vivo.

Abstract: A DNA segment of a gene coding for a signal peptide is disclosed the segment is to be used in a host-vector system employing a bacterium belonging to the genus Streptomyces as a host by incorporation in the vector DNA. The segment comprises a DNA having a base sequence coding for the peptide having the amino acid sequence from X to Y in the annexed FIG. 1.A vector plasmid to be used for transformation of bacteria belonging to the genus Streptomyces is also disclosed. The plasmid comprises a DNA segment with a base sequence coding for an extra-cellular .alpha.-amylase derived from Streptomyces hygroscopicus SF-1084 strain or a mutant thereof the DNA segment incorporated into a vector plasmid is to be used in a host-vector system employing a bacterium belonging to the genus Streptomyces as a host and also having a DNA segment necessary for expression of the gene information of the DNA segment.

Abstract: Cephalosporin compounds, intermediate compounds therefor, and processes for preparation thereof are described; the compounds have the formula (I) ##STR1## wherein R.sub.1 and R.sub.2 can each represent hydrogen, a hydroxyl group, a lower alkoxy group, or a substituted or unsubstituted phenylalkoxy group; R.sub.3 represents hydrogen or a lower alkyl group; R.sub.4 represents hydrogen or a hydroxyl group; and R.sub.5 represents ##STR2## wherein R.sub.6 is hydrogen, a lower alkyl group, an aminoalkyl group, an aminoaralkyl group, a --(CH.sub.2).sub.n --SO.sub.3 Na group, or a --(CH.sub.2).sub.n --COR.sub.9 group [wherein R.sub.9 is a hydroxyl group, an OM group (wherein M is an alkali metal), an alkoxy group, or an ##STR3## group, (wherein R.sub.10 and R.sub.11, which may be the same or different, can represent hydrogen or an alkyl group), and n is 0 or an integer of from 1 to 4]; R.sub.7 is hydrogen, a lower alkyl group, an amino group, or a substituted or unsubstituted aryl group; and R.sub.

Abstract: Penicillin compounds and methods for the production thereof are described, said penicillin compounds being represented by the formula (I) ##STR1## wherein R.sub.1, R.sub.2, and R.sub.3 each represents hydrogen, a lower alkyl group, a halogen atom, a lower alkoxy group, a hydroxyl group, or a substituted or unsubstituted phenylalkoxy group except that R.sub.1, R.sub.2, and R.sub.3 cannot all represent hydrogen simultaneously; R.sub.4 represents hydrogen or a lower alkyl group; and R.sub.5 represents hydrogen or a hydroxyl group.

Abstract: Novel cephalosporin derivatives having formulae (V) and (III): ##STR1## wherein R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.8 and A are defined as in the specification.