Abstract: An apparatus for treating semiconductor wafers utilizing a plasma generated by electron cyclotron resonance (ECR) is disclosed in which a microwave is supplied to a plasma generating chamber via a rectangular waveguide, a rectangular-to-circular microwave converter, and a circular polarization converter. The polarization converter may comprise a phase shift plate of a dielectric material or an electrically conductive material disposed in a circular waveguide in the form of a metallic cylinder. The polarization converter transforms a circular TE.sub.11 mode microwave supplied from the rectangular-to-circular microwave converter to a circularly polarized one by rotating the direction of the electric field of the microwave in the TE.sub.11 mode one complete turn in one period of the microwave.

Abstract: Novel 1-(imidazo[1,2-a]pyridin-6-yl)-2-alkanone derivatives and (imidazo [1,2-a]pyridin-6-yl) acetaldehyde derivatives are provided. The novel derivatives are intermediates for the production of 5-(6-imidazo[1,2-a]pyridyl)pyridine derivatives which are useful as cardiotonics.

Abstract: 5-(6-Imidazo[1,2-a]pyridyl)pyridine derivatives represented by general formula: ##STR1## wherein X represents hydrogen atom or methyl group; Y represents cyano group, carboxamido group, hydrogen atom, amino group or a halogen atom; Z represents hydrogen atom or a lower alkyl group; W represents hydrogen atom or a lower alkyl group; R.sup.1 represents hydrogen atom, a lower alkyl group, phenyl group, a group shown by formula: --CH.sub.2 R.sup.4 in which R.sup.4 is a lower alkoxy group, or a group shown by formula: ##STR2## in which R.sup.5 and R.sup.6 are hydrogen atom or a lower alkyl group; R.sup.2 represents hydrogen atom or a halogen atom; and R.sup.3 represents hydrogen atom, a lower alkyl group or a halogen atom; or a tautomer thereof; and pharmacologically acceptable salts thereof are disclosed. The 5-(6-imidazo[1,2-a]pyridyl) pyridine derivatives are effective for treating congestive heart failures.

Abstract: 5-(6-Imidazo[1,2-a]pyridyl)pyridine derivatives represented by general formula: ##STR1## wherein X represents hydrogen atom or methyl group; Y represents cyano group, carboxamido group, hydrogen atom, amino group or a halogen atom; Z represents hydrogen atom or a lower alkyl group; W represents hydrogen atom or a lower alkyl group; R.sup.1 represents hydrogen atom, a lower alkyl group, phenyl group, a group shown by formula: --CH.sub.2 R.sup.4 in which R.sup.4 is a lower alkoxy group, or a group shown by formula: ##STR2## in which R.sup.5 and R.sup.6 are hydrogen atom or a lower alkyl group;R.sup.2 represents hydrogen atom or a halogen atom; and R.sup.3 represents hydrogen atom, a lower alkyl group or a halogen atom; or a tautomer thereof; and pharmacologically acceptable salts thereof are disclosed. The 5-(6-imidazo[1,2-a]pyridyl) pyridine derivatives are effective for treating congestive heart failures.

Abstract: 5-(6-Imidazo[1,2-a]pyridyl)pyridine derivatives represented by general formula: ##STR1## wherein X represents hydrogen atom or methyl group; Y represents cyano group, carboxamido group, hydrogen atom, amino group or a halogen atom; Z represents hydrogen atom or a lower alkyl group; W represents hydrogen atom or a lower alkyl group; R.sup.1 represents hydrogen atom, a lower alkyl group, phenyl group, a group shown by formula: --CH.sub.2 R.sup.4 in which R.sup.4 is a lower alkoxy group, or a group shown by formula: ##STR2## in which R.sup.5 and R.sup.6 are hydrogen atom or a lower alkyl group R.sup.2 represents hydrogen atom or a halogen atom; and R.sup.3 represents hydrogen atom, a lower alkyl group or a halogen atom; or a tautomer thereof; and pharmacologically acceptable salts thereof are disclosed. The 5-(6-imidazo[1,2-a]pyridyl)pyridine derivatives are effective for treating congestive heart failures.