Abstract: This surface treatment method comprises a rustproofing step, a rinsing step, and a cleaning step. In the rustproofing step, a rustproofing liquid containing orthophosphoric acid and an organic acid is used to perform a rustproofing treatment on the surface of a steel material. In the rinsing step, a treatment liquid containing an oxo acid salt of a transition metal is used to perform a rinsing treatment on the surface of the steel material. In the cleaning step, the surface of the steel material that has undergone the rinsing step is subjected to a cleaning treatment.

Abstract: This surface treatment method comprises a rustproofing step, a rinsing step, and a cleaning step. In the rustproofing step, a rustproofing liquid containing orthophosphoric acid and an organic acid is used to perform a rustproofing treatment on the surface of a steel material. In the rinsing step, a treatment liquid containing an oxo acid salt of a transition metal is used to perform a rinsing treatment on the surface of the steel material. In the cleaning step, the surface of the steel material that has undergone the rinsing step is subjected to a cleaning treatment.

Abstract: This invention relates to a process for the preparation of a 6,7-diacyl-7-deacetylforskolin derivative represented by the general formula: ##STR1## wherein R.sup.1 and R.sup.2 each stands for an acyl group and R.sup.3 stands for an aliphatic group having 2 to 3 carbon atoms, which comprises eliminating the acyl group at position 1 in a 1,6,7-triacyl-7-deacetylforskolin derivative represented by the general formula: ##STR2## wherein R.sup.1, R.sup.2 and R.sup.3 are as defined above, by solvolysis. The compound of the formula (I) is expected as medicine.

Abstract: This invention relates to a process for the preparation of a 6,7-diacyl-7-deacetylforskolin derivative represented by the general formula: ##STR1## wherein R.sup.1 and R.sup.2 each stands for an acyl group and R.sup.3 stands for an aliphatic group having 2 to 3 carbon atoms, which comprises eliminating the acyl group at position 1 in a 1,6,7-triacyl-7-deacetylforskolin derivative represented by the general formula: ##STR2## wherein R.sup.1, R.sup.2 and R.sup.3 are as defined above, by solvolysis. The compound of the formula (I) is expected as medicine.

Abstract: A novel nucleic acid derivative represented by the following general formula (I) and physiologically acceptable salt thereof which are expected to have an antiviral activity: ##STR1## wherein B represents a nucleic acid base derivative; A.sup.1 and A.sup.2 represent, independently of each other, OR.sup.1 or OCOR.sup.1 ; R.sup.1 represents a hydrogen atom, a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group; l represents a number of 0 or 1; and m and n each represents an integer of 0-2; provided that when l and m are 0, n is 0 or 2.

Abstract: This invention relates to cyclobutane derivatives represented by the following general formula (1) and physiologically acceptable salts thereof: ##STR1## wherein B represents a nucleic acid base derivative, R.sup.1 and R.sup.2 independently represent hydrogen atom, dialkylaminoacyl group, 1,4-dihydro-1-methylnicotinoyl group or substituted phosphoric acid group, provided that either one of R.sup.1 and R.sup.2 is a group other than hydrogen atom.The compounds of this invention exhibit a high oral absorbability and are metabolized in vivo into the compounds of formula (1a). Accordingly, the compounds of this invention are expectedly useful as antiviral agent.

Abstract: This invention relates to a process for the preparation of a 6,7-diacyl-7-deacetylforskolin derivative represented by the general formula: ##STR1## wherein R.sup.1 and R.sup.2 each stands for an acyl group and R.sup.3 stands for an aliphatic group having 2 to 3 carbon atoms, which comprises eliminating the acyl group at position 1 in a 1,6,7-triacyl-7-deacetylforskolin derivative represented by the general formula: ##STR2## wherein R.sup.1, R.sup.2 and R.sup.3 are as defined above, by solvolysis. The compound of the formula (I) is expected as medicine.

Abstract: A chroman derivative represented by the following general formula [1]: ##STR1## wherein R.sub.1 represents cyano group, nitro group, halogenomethyl group or --SO.sub.2 --X group (X represents lower alkyl group having 1-6 carbon atoms or aryl group); R.sub.2 represents hydrogen atom or OA group (A represents hydrogen atom, nitro group, lower acyl group having 1-6 carbon atoms, arylcarbonyl group, lower alkylsulfonyl group having 1-6 carbon atoms, arylsulfonyl group, arylalkyl group, tetrahydropyranyl group, lower alkoxycarbonyl group having 1-6 carbon atoms, arylalkoxycarbonyl group or silyl derivative group); R.sub.3 singly represents a hydrogen atom; or R.sub.3 forms a bond jointly with R.sub.2 ; and R.sub.4, R.sub.5, R.sub.6 and R.sub.7 each represent hydrogen atom, vinyl group, formyl group, --Y--(OA).sub.n group (Y represents straight or branched chain alkylene group having 1-6 carbon atoms or lower alkenyl group having 1-6 carbon atoms, A is as defined above, and n represents an integer of 1-3.

Abstract: This invention relates to a process for producing an optically active cyclobutylamine which comprises reacting a racemic modification of cyclobuthylamine represented by the following general formula [I]: ##STR1## wherein R.sup.1 and R.sup.2 represent each a hydrogen atom or a protecting group; with an optically active N-acylphenylglycine to thereby give two corresponding diastereomeric salts, crystallizing the more difficultly soluble diastereomeric salt and isolating the corresponding optically active cyclobutylamine from the diastereomeric salt thus crystallized. The optically active substances of the compound of the above general formula [I] are useful as, for example, an intermediate in the synthesis of 9-[(1R, 2R, 3S)-2,3-bis(hydroxymethyl)-1-cyclobutyl]guanine which is expected as an antiviral agent.

Abstract: A process for producing an optically active aminoketone derivative having a central muscle relaxant activity is described wherein a racemic mixture of the aminoketone is reacted with optically active L-acetylphenylglycine and then isolating the optically active L-aminoketone from the diastereomeric salts formed by the reaction.

Abstract: A new class of aminoketone derivatives according to the formula: ##STR1## and certain propiophenone derivatives in particular, corresponding to the formula: ##STR2## having central muscle relaxant activity.

Abstract: This invention relates to forskolin derivatives, their physiologically acceptable salts, and a process for producing these compounds. The forskolin derivative is represented by the general formula ##STR1## wherein; I. when R.sup.1 is hydrogen and R.sup.4 is vinyl, ethyl, or cyclopropyl,(1) either of R.sup.2 and R.sup.3 denotes a residue represented by the formula ##STR2## wherein each of R.sup.5 and R.sup.6 denotes hydrogen or lower alkyl or R.sup.5 and R.sup.6 combine with each other to form a lower alkylene chain which may or may not contain an oxygen or nitrogen atom and m is an integer of 1 to 5, and the other one of R.sup.2 and R.sup.3 denotes hydrogen or a residue represented by the formula CO(CH.sub.2).sub.n X, X being hydrogen or ##STR3## wherein, each of R.sup.7 and R.sup.8 denotes hydrogen or lower alkyl or R.sup.7 and R.sup.8 combine with each other to form a lower alkylene chain which may or may not contain an oxygen or nitrogen atom, and n being an integer of 1 to 5, or(2) R.sup.

Abstract: The present invention relates to a phenylpiperazine derivative represented by the general formula: ##STR1## wherein R.sub.1 stands for a lower alkyl group; R.sub.2 stands for a group represented by the general formula: ##STR2## (wherein R.sub.3, R.sub.4 and R.sub.5 each stand for a hydrogen atom or a lower alkyl group and Y stands for CH or N); and n stands for an integer of 1 to 6,and pharmaceutically acceptable acid addition salts thereof, which exhibit an .alpha..sub.1 -blocking activity and therefore are expected to be useful as a hypotensive drug.

Abstract: This invention relates to the novel 1,6-naphthyridine derivatives useful as antidinic and/or cerebral circulation improver, such novel derivatives being represented by the following general formula: ##STR1## (wherein R is a C.sub.2-10 alkyl which may have hydroxyl, lower alkylcarbonyl, lower alkyloxycarbonyl or phenoxy as a substituent; a C.sub.2-10 unsaturated aliphatic hydrocarbon group having unsaturated double bond(s); a phenyl-lower alkyl which may have halogen, lower alkyl, lower alkoxy or lower alkylthio as substituent(s) attached to the phenyl ring; a cinnamyl which may have halogen, nitro, lower alkyl or lower alkoxy as substituent(s) attached to the phenyl ring; propargyl; 1-naphthylmethyl; 2-thenyl; cyclohexenyl; a cycloalkyl-lower alkyl with a 3- to 6-membered ring; 1/2(C.sub.2-4 alkylene); 1/2(butenylene), or diphenylmethyl, and in case two alkoxyl groups are present attached to the phenyl ring, they may be bonded to form a ring) and salt thereof.

Abstract: Novel .alpha.-methyl-.beta.-aminopropiophenone derivatives having bronchodilator activity represented by the following general formula: ##STR1## where R represents alkyl having 1-6 carbon atom benzyl or phenyl; R.sub.1 and R.sub.2 individually represent alkyl having 1-6 carbon atom or they form, joining to each other together with the adjacent nitrogen atom with or without intervening an atom other than carbon atom, a saturated heterocyclic ring which may be substituted with lower alkyl; n is an integer of 0, 1 or 2 on the proviso that R represents methyl or ethyl if n is 0, as well as their non-toxic salts are presented. Method of producing the new derivatives and the bronchodilatation method using them are disclosed as well.