Abstract: New campotothecin derivatives and a process for preparing same are disclosed, which are represented by the general formula: ##STR1## wherein R.sup.1 represents a lower alkyl group, R.sup.2 represents a hydrogen atom or an amino, hydroxyl, lower acylamino or lower alkoxy group, R.sup.3 represents a hydrogen or halogen atom or a lower alkyl, hydroxyl, lower alkoxy, nitro, amino, cyano or di(lower alkyl)amino group, R.sup.4 represents a hydrogen or halogen atom or a lower alkyl, hydroxyl, lower alkoxy, lower alkylthio, amino, cyano or di(lower alkyl)amino group, and R.sup.5 represents a hydrogen or halogen atom or a hydroxyl or lower alkoxy group, with the proviso that all of the R.sup.2, R.sup.3, R.sup.4 and R.sup.5 substituents should not be a hydrogen atom and also that if any one of the R.sup.2, R.sup.3, R.sup.4 and R.sup.5 is a hydroxyl or lower alkoxy group, all of the other three substituents should not be a hydrogen atom.

Abstract: A 2-alkynyladenosine represented by general formula [I]: ##STR1## wherein n is an integer of from 2 to 15, has been found to have excellent properties as an antihypertensive agent. On the basis of this finding, the present invention has provided an antihypertensive agent comprising an antihypertensive effective amount of a compound of the above formula [I] and a pharmaceutically acceptable carrier. The present invention also discloses a novel compound 2-alkynyladenosine of formula [I] shown above wherein n is 6 to 15.

Abstract: In a common drive output circuit for driving dissimilar switching semiconductor devices having different drive input characteristics by turning on and off dc power supplies to apply a voltage between the drive input terminals of either one of the switching semiconductor devices through two transistors connected in a Darlington pair, the collector circuit of one of the two transistors which is not at the output stage has a diode inserted in series which has such a polarity as to permit passage of the collector current.

Abstract: New camptothecin derivatives, useful as antitumor agents or intermediates therefor, of the general formula (I) ##STR1## wherein X is a lower alkyl group, and R is a hydrogen atom or the grouping -COY where Y is a linear or branched unsubstituted C.sub.1 -C.sub.18 alkyl group; a lower alkyl group substituted by a halogen atom or a lower alkylthio, amino, acylamino, hydroxyl, lower alkoxy, aryloxy or lower alkoxycarbonyl group; a C.sub.3 -C.sub.19 alkenyl, C.sub.3 -C.sub.19 alkynyl or C.sub.3 -C.sub.8 cycloalkyl group; a C.sub.3 -C.sub.

Abstract: Disclosed is a process for preparing a 3-hydroxy-7-mercaptopyrazolo[4,3-d]pyrimidine compound represented by the general formula (IX): ##STR1## wherein R.sup.1 is a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, a phenyl group or a substituted phenyl group, which comprises:from a pyrazole compound represented by the general formula (III): ##STR2## wherein R.sup.1 is the same as defined above. Also disclosed are pyrazole compounds represented by the general formula (I): ##STR3## The compounds serve as intermediate for preparing the compound of the formula (IX).

Abstract: A pyrazolo[4,3-d]pyrimidine derivative having the formula: ##STR1## wherein R.sup.1 is lower alkyl or phenyl which is unsubstituted or substituted by lower alkyl, lower alkoxy or halogen; R.sup.2 is a saturated or unsaturated, straight chain or branched aliphatic group having from 2 to 22 carbon atoms or phenyl-lower alkyl with the phenyl group unsubstituted or substituted by lower alkyl, lower alkoxy or halogen; and A is an alkylene group having from 1 to 3 carbon atoms which is unsubstituted or substituted by methyl, or a pharmaceutically acceptable salt thereof.

Abstract: A pyrazolo[4,3-d]pyrimidine derivative having the formula: ##STR1## wherein R.sup.1 is lower alkyl or phenyl, R.sup.2 is --A--CO.sub.2 R.sup.21 (wherein A is alkylene having from 1 to 10 carbon atoms which is unsubstituted or substituted by alkyl having from 1 to 3 carbon atoms; and R.sup.21 is lower alkyl having from 1 to 4 carbon atoms), --CH.sub.2 CO-phenyl, a saturated or unsaturated, straight chain or branched aliphatic group having from 3 to 16 carbon atoms, phenyl-lower alkyl, --CH.sub.2 CN, chloro substituted phenyl-lower alkyl or ##STR2## (wherein R.sup.22 is hydrogen or lower alkyl), and R.sup.3 is a saturated or unsaturated, straight chain or branched aliphatic group having from 2 to 22 carbon atoms, phenyl-lower alkyl, benzyloxy substituted phenyl-lower alkyl, lower alkyl substituted or unsubstituted 2-(phenylmethyloxy)ethyl, cyclohexylcyclohexyl, methylcyclohexyl, 3-thia-n-heptyl, 3,6-dioxa-n-decyl, 4-oxo-n-pentyl or 2-hydroxyethyl.

Abstract: New camptothecin derivatives possessing high anti-tumor activity with slight toxicity, represented by the general formula: ##STR1## wherein R.sup.1 is a hydrogen atom, a halogen atom or an alkyl group with 1-4 carbon atoms and X is a chlorine atom or --NR.sup.2 R.sup.3 where R.sup.2 and R.sup.3 are the same or different and each represents a hydrogen atom, a substituted or unsubstituted alkyl group with 1-4 carbon atoms or a substituted or unsubstituted carbocyclic or heterocyclic group, with the proviso that when both R.sup.2 and R.sup.3 are the substituted or unsubstituted alkyl groups, they may be combined together with the nitrogen atom, to which they are bonded, to form a heterocyclic ring which may be interrupted with --O--, --S-- and/or >N--R.sup.4 in which R.sup.

Abstract: New Camptothecin derivatives possessing high anti-tumor activity with slight toxicity, represented by the general formula: ##STR1## wherein R.sup.1 stands for a hydrogen atom, an alkyl group, a hydroxyl group, an alkoxy group or an acyloxy group, R.sup.2 for a hydrogen atom, an alkyl group, an aralkyl group, a hydroxymethyl group, a carboxymethyl group or an acyloxymethyl group, and R.sup.3 for the grouping --XR' (where R' is a hydrogen atom, an alkyl group or an acyl group and X is an oxygen atom or a sulfur atom), a nitro group, an amino group, an alkylamino group, an acylamino group or a halogen atom, with the proviso that when both of R.sup.1 and R.sup.2 are hydrogen atoms, R.sup.3 should not be hydroxyl group, methoxy group or acetoxy group. These new camptothecin derivatives are prepared by treating a 5-R.sup.1 -7-R.sup.2 camptothecin derivative with a peroxidant and then reacting the resultant 5-R.sup.1 -7-R.sup.

Abstract: New 5- and/or 7-substituted camptothecin-1-oxide derivatives possessing anti-tumor activity with slight toxicity, represented by the general formula: ##STR1## wherein R is a hydrogen atom, an alkyl group, a hydroxyl group, an alkoxy group or an acyloxy group and R' is a hydrogen atom, an alkyl group, an aralkyl group, a hydroxymethyl group, an acyloxymethyl group or a carboxymethyl group, with the proviso that both of R and R' should not be hydrogen atoms. These 5- and/or 7-substituted camptothecin-1-oxide derivatives are prepared by treating the corresponding 5- and/or 7-substituted camptothecins with a peroxidant as an N-oxidizing reagent.

Abstract: New Camptothecin derivatives possessing high anti-tumor activity with slight toxicity, represented by the general formula: ##STR1## wherein R.sup.1 is a hydrogen atom, an alkyl group, a hydroxyl group, an alkoxy group or an acyloxy group, R.sup.2 for a hydrogen atom, an alkyl group, an aralkyl group, a hydroxymethyl group, a carboxymethyl group or an acyloxymethyl group, and R.sup.3 is the grouping --XR' (where R' is a hydrogen atom, an alkyl group or an acyl group and X is an oxygen atom or a sulfur atom), a nitro group, an amino group, an alkylamino group, an acylamino group or a halogen atom, with the proviso that when both of R.sup.1 and R.sup.2 are hydrogen atoms, R.sup.3 should not be a hydroxyl group, methoxy group or acetoxy group. These new camptothecin derivatives are prepared by treating a 5-R.sup.1 -7-R.sup.2 -camptothecin derivative with a peroxidant and then reacting the resultant 5-R.sup.1 -7-R.sup.

Abstract: New camptothecin derivatives possessing either or both of high anti-tumor activity and slight toxicity, represented by the general formula: ##STR1## wherein X is H, CH.sub.2 OH, COOH, an alkyl group, an aralkyl group or the grouping CH.sub.2 OR.sup.1 or COOR.sup.2 wherein R.sup.1 is an alkyl group or an acyl group and R.sup.2 is a lower alkyl group, Y is H, OH or the grouping OR.sup.3 wherein R.sup.3 is a lower alkyl group or an acyl group, and Z is H or an acyl group, with the proviso that when X is CH.sub.2 OH, an alkyl group or an aralkyl group, both Y and Z are H, that when X is the grouping CH.sub.2 OR.sup.1 or COOR.sup.2, Y is H, that when Y is OH, both X and Z are H, and that when Y is the grouping OR.sup.3, X is H, and water-soluble alkali metal salts thereof.

Abstract: New 7-substituted camptothecin derivatives possessing anti-tumor activity with slight toxicity, represented by the general formula: ##STR1## wherein R stands for --CHO, --CH.sub.2 OR', --CH(OR').sub.2 or --CH.dbd.N--X where R' is a lower alkyl group with 1-6 carbon atoms or a phenylalkyl group with 1-3 carbon atoms in the alkylene moiety thereof, and X is a hydroxyl group or --NR.sup.1 R.sup.2 where R.sup.1 and R.sup.2 are the same or different and each represents a hydrogen atom or a lower alkyl group with 1-6 carbon atoms, or when R.sup.1 is hydrogen, R.sup.2 may be a lower alkyl group with 1-6 carbon atoms, a substituted or unsubstituted aryl group, a carbamoyl group, an acyl group, an aminoalkyl group or an amidino group, or when R.sup.1 is the lower alkyl group, R.sup.2 may be an aminoalkyl group, or R.sup.1 and R.sup.2 may be combined together with the nitrogen atom, to which R.sup.1 and R.sup.2 are bound, to form a heterocyclic group, and quaternary salts thereof.

Abstract: New camptothecin derivatives possessing either or both of high anti-tumor activity and slight toxicity, represented by the general formula: ##STR1## wherein X is H, CH.sub.2 OH, COOH, an alkyl group, an aralkyl group or the grouping CH.sub.2 OR.sup.1 or COOR.sup.2 wherein R.sup.1 is an alkyl group or an acyl group and R.sup.2 is a lower alkyl group, Y is H, OH or the grouping OR.sup.3 wherein R.sup.3 is a lower alkyl group or an acyl group, and Z is H or an acyl group, with the proviso that when X is CH.sub.2 OH, an alkyl group or an aralkyl group, both Y and Z are H, that when X is the grouping CH.sub.2 OR.sup.1 or COOR.sup.2, Y is H, that when Y is OH, both X and Z are H, .[.and.]. that when Y is the grouping OR.sup.3, X is H, .Iadd.and that X, Y and Z are not each simultaneously hydrogen, .Iaddend.and water-soluble alkali metal salts thereof.