Abstract: There is provided a stamper for producing a recording medium exhibiting excellent durability and capable of stably forming projections and pits and a method of producing the stamper. A stamper for producing a recording medium comprising projections and pits in a predetermined pattern on the surface thereof, wherein a value of tan .theta..sup.-1 obtainable from an enlargement angle .theta. of an output from a cartridge with respect to an enlargement of an output denoting a load measured by a test of scratching the surface having the projections and pits under conditions that a diameter of a stylus is 100 .mu.m and a loading speed of 1 .mu.m/second is 1.3 or more.

Abstract: A floppy disk unit including a cartridge case or a jacket, a flexible magnetic disk rotatably accommodated in the cartridge case or the jacket, and liners disposed on the inner surface of the cartridge case or the jacket, wherein at least the surface layer of each of the liners in sliding contact with the magnetic disk is made from a fiber material such as rayon fiber, polyamide fiber, polyester fiber, or polynosic rayon fiber, each fiber having a diameter of 10 to 30 .mu.m, and the fiber material contains inorganic oxide material powder such as titanium oxide having an average diameter of 0.01 to 1 .mu.m by weight ratio 0.1 to 10%.

Abstract: This invention relates to a 1,4-dihydropyridine-3,5-dicarboxylate derivative represented by the following general formula (I): ##STR1## wherein R means an imidazolyl or pyridyl group, R.sub.1 denotes a hydrogen or halogen atom or a nitro or trifluoromethyl group, R.sub.2 is a lower alkyl group, X is CH or N, A means a lower alkylene group, ##STR2## B being a lower alkylene or O-lower alkylene group, ##STR3## R.sub.4 being a hydrogen atom or lower alkyl group, or ##STR4## m denotes a number of 1-3, and n stands for 1 or 2. The derivative has vasodilative effects, hyperkinemic effects, platelet aggregation inhibitory effects, thromboxane A.sub.2 formation inhibitory effects and so on, and are hence useful as a pharmaceutical product such as vasodilator, antihypertensive, antithrombotic agent, antiarteriosclerotic agent or the like.

Abstract: A novel racemate K-351A composed of an optical isomer (2'S),(3S)K-351 [3,4-dihydro-8-(2'-hydroxy-3'-isopropylamino)propoxy-3-nitroxy-2H-1-benzop yran] and (2'R),(3R)K-351, a novel racemate K-351B composed of an optical isomer (2'R),(3S)K-351 and (2'S),(3R)K351 and an acid addition salt of these two novel racemates; a process for converting the two racemates to each other; and also to a pharmaceutical composition comprising each of the two racemates useful for the treatment of cardiovascular diseases.

Abstract: An optical isomer selected from the group consisting of (2'R),(3R)-3,4-dihydro-8-(2'-hydroxy-3'-isopropylamino)propoxy-3-nitroxy-2 H-1-benzopyran, (2'S),(3R)-3,4-dihydro-8-(2'-hydroxy-3'-isopropylamino)propoxy-3-nitroxy-2 H-1-benzopyran and acid addition salts of these isomers, process for producing these isomers and a pharmaceutical composition thereof useful for the treatment of cardiovascular diseases.

Abstract: Phenyl tetrahydronaphthylcarboxylate of the formula: ##STR1## wherein A is a direct bond, or a lower alkylene, vinylene or imino group; B is a direct bond, a lower alkylene or --NH-lower alkylene group, or an --OCH.sub.2 CO-- residual group; and R is a lower alkyl group, with the proviso that A and B are not direct bonds simultaneously, and A, B and R are not a lower alkylene group, a direct bond and a methyl group, respectively, at the same time, are effectively useful as chymotrypsin inhibitors.

Abstract: Benzoyl indolecarboxylates of the formula: ##STR1## where R.sup.1 is hydrogen, halogen, lower alkyl or lower alkoxy; R.sup.2 is hydrogen, lower alkyl, acetyl or benzoyl; R.sup.3 is hydrogen or lower alkyl; and A is a direct bond, or lower alkylene or vinylene substituted at the 2-, 3- or 5-position of the indole nucleus, are effective agents as chymotrypsin inhibitors.

Abstract: An azetidine derivative of the formula, ##STR1## wherein R is a hydrogen atom or a hydroxyl group, and R.sub.a, R.sub.b, R.sub.c, R.sub.a ', R.sub.b ' and R.sub.c ' are identical or different and each are a lower alkyl group.

Abstract: A compound represented by the following formula ##STR1## wherein R represents a lower alkyl group having 2 to 6 carbon atoms, and n is an integer of from 1 to 5.

Abstract: A piperazine derivartive represented by the following formula: ##STR1## wherein R.sub.1 : an indolyl group which may optionally be substituted by one or more lower alkyl and/or lower alkoxy groups, naphthyl group which may optionally be saturated partially with 2 or 4 hydrogen atoms, or phenyl or cyclohexyl group which may optionally be substituted by one or more lower alkyl groups;A: a single bond or alkylene group;P: a single bond or vinylene group;Q: an -O-alkylene group or -NH-alkylene group when P is a single bond, or a single bond when P is a vinylene group; andR.sub.2 : a lower alkyl, morpholino-lower alkyl, morpholino-carbonyl lower alkyl, piperidinocarbonyl lower alkyl, piperazinocarbonyl lower alkyl or lower alkylaminocarbonyl lower alkyl group, or an acid addition salt thereof is a proteolytic enzyme inhibitor.