Abstract: New compounds, 2',3'-dideoxy-2'-fluorokanamycin A and 1-N-(.alpha.-hydroxy-.omega.-aminoalkanoyl) derivatives thereof, particularly 1-N-(DL- or L-3-amino-2-hydroxypropionyl)- and 1-N-(L-4-amino-2-hydroxybutyryl)-2',3'-dideoxy-2'-fluorokanamycins A are now provided, which are each useful as antibacterial agent. 2',3'-Dideoxy-2'-fluorokanamycin A is prepared by a process comprising condensing a 6-azido-4-O-protected-2,3,6-trideoxy-2-fluoro-.alpha.-D-ribo-hexopyranosyl bromide with the 4-hydroxyl group of a 6-O-(2',4',6'-tri-O-protected-3'-N-protected-3'-amino-3'-deoxy-.alpha.-D-g lucopyranosyl)-1,3-bis-N-protected-2-deoxystreptamine, reducing the resulting condensation product to convert its azido group into an amino group, and removing the remaining amino-protecting and hydroxyl-protecting groups from the reduction product.

Abstract: A new compound, 3'-fluoro-3'-deoxykanamycin A is now provided, which is active against gram-negative and gram-positive bacteria, including kanamycin-resistant strains of bacteria and is useful as antibacterial agent for therapeutic treatment of bacterial infections. This new compound is produced by a process comprising reacting a 6-azido-2,4-di-O-protected-3,6-dideoxy-3-fluoro-.alpha.-D-glucopyranosyl bromide with the 4-hydroxyl group of a 6-O-(2'-O-protected-3'-N-protected-3'-amino-4',6'-di-O-protected-3'-deoxy- .alpha.-D-glucopyranosyl)-1,3-bis-N-protected-2-deoxystreptamine, reducing the azido group of the resulting reaction product into an amino group, and removing the remaining protective groups from the reduction product.

Abstract: Novel 23-C-substituted mycaminosyl tylonolide of the general formula (I) ##STR1## wherein R.sup.1 represents a lower alkyl group, an aryl group, a lower alkenyl group or a lower alkynyl group, R.sup.2 represents a hydrogen atom or a hydroxyl group.These compounds have excellent antibacterial activities.

Abstract: 1-N-(L-3-amino-2-hydroxypropionyl)-2',-3'-dideoxykanamycin A and 1-N-(L-4-amino-2-hydroxybutyryl)-2',3'-dideoxykanamycin A are now provided which each is a new compound useful as antibacterial agent. The new compounds each is produced by acylating the 1-amino group of 2',3'-dideoxykanamycin A with L-3-amino-2-hydroxypropionic or L-4-amino-2-hydroxybutyric acid.

Abstract: Tylosin compounds of the formula ##STR1## wherein R.sub.1 represents a hydroxyl group; a halogen atom; ##STR2## group (wherein R.sub.5 is a hydrogen atom or a lower alkyl group which may be substituted by a hydroxyl group and R.sub.6 is a hydrogen atom, a lower alkyl group which may be substituted by a hydroxyl group, an aryl group, an aralkyl group, a cycloalkyl group having 3-10 carbon atoms, --CO(O).sub.m --R.sub.7 group (wherein m is 0 or 1 and R.sub.7 is a lower alkyl group, an aryl group, an aralkyl group, a furanyl group, or a pyridyl group), or --CH.sub.2 --R.sub.13 group (wherein R.sub.13 is a mono-, di-, or trifluoromethyl group)); --N(CH.sub.2).sub.n group (wherein n is an integer of 2-15) which may be substituted by an oxo group, a hydroxyl group, a lower alkyl group, or a hydroxy lower alkyl group; an imidazolyl group, a morpholino group, or a piperazino group each may be substituted by a lower alkyl group; or --OOCCH.sub.2 --R.sub.8 group (wherein R.sub.8 is ##STR3## group (wherein R.sub.

Abstract: A new semi-synthetic antibiotic, 3"-deoxystreptomycin is now provided, which is useful as an antibacterial agent and is produced from 3"-deoxydihydrostreptomycin by a process comprising oxidizing the 3'-hydroxymethyl group of 2,5,6,4",6"-penta-O-acetyl-2"-N-benzyloxycarbonyl-3"-deoxydihydrostreptomy cin as prepared by skilled introduction of amino-protecting group and hydroxyl-protecting group of appropriately selected natures into 3"-deoxydihydrostreptomycin, and then removing the protective groups from the oxidation product, 2,5,6,4",6"-penta-O-acetyl-2"-N-benzyloxycarbonyl-3"-deoxystreptomycin.

Abstract: New semi-synthetic antibiotics, 3"-epistreptomycin and 3"-epidihydrostreptomycin are now provided, which are useful as antibacterial agents. 3"-Epidihydrostreptomycin is produced by a process comprising hydrolyzing an appropriately N,O-protected 2",3"-N,O-carbonyl-3"-epidihydrostreptomycin which is prepared by skilled introduction of amino-protecting groups and hydroxyl-protecting groups of appropriately selected natures into dihydrostreptomycin and intermolecular condensation of a particular pair of amino-protecting and hydroxyl-protecting groups so introduced. 3"-Epistreptomycin is produced by a process comprising oxidizing the 3'-hydroxymethyl group of an appropriately N,O-protected 3"-epidihydrostreptomycin as prepared by skilled introduction of amino-protecting groups and hydroxyl-protecting groups of appropriately selected natures, and then removing the remaining protective groups from the resultant N,O-protected 3"-epistreptomycin obtained as the oxidation product.

Abstract: 2'-Modified kanamycins, including 2'-deoxykanamycin A, 2'-epikanamycin A and 2'-epikanamycin B, as new compounds are produced starting from kanamycin A by consecutive reaction steps. These new compounds are useful as antibacterial agent.

Abstract: An aminoglycoside compound of the following formula ##STR1## wherein one of R.sub.1 and R.sub.2 represents a hydrogen atom and the other, a methyl group, R.sub.3 represents a hydrogen atom or an amino acyl group having 2 to 5 carbon atoms, R.sub.4 represents a lower alkyl group substituted by one or two substituents selected from the class consisting of hydroxy and amino groups, or a hexopyranosyl group whose hydroxy groups may be substituted by amino groups,and a pharmaceutically acceptable acid addition salt thereof; and an antibiotic composition comprising said compound and its pharmaceutically acceptable acid addition salt.

Abstract: Tylosin derivatives shown by the general formula ##STR1## wherein R represents a hydrogen atom or a hydroxyl group; R.sub.1 represents a halogen atom, a hydroxyl group, a tetrahydrofuranyloxy group, a tetrahydropyranyloxy group, a tetrahydrothiofuranyloxy group, a tetrahydrothiopyranyloxy group, an alkanoyloxy group, an arylcarbonyloxy group, an aralkylcarbonyloxy group, a lower alkylthiomethyloxy group, a heterocyclic thio group which may have a substituent, a mono- or di- lower alkylamino lower alkylthio group or a group of ##STR2## (wherein R.sub.4 represents a hydroxyl group or an alkanoyloxy group); R.sub.2 represents a hydrogen atom, a hydroxyl group, or an alkanoyloxy group; R.sub.3 represents a hydroxyl group or an alkanoyloxy group; and represents a single bond or a double bond, but represents a double bond when R.sub.2 is a hydrogen atom.These compounds are useful as antibiotics.

Abstract: 3'-Deoxykanamycin A useful as an antibacterial agent can be produced by a new process comprising reacting a 2',2"-di-O-acylated-3'-O-sulfonylated-tetra-N-protected derivative of kanamycin A with a base such as alkali metal alcoholate in a lower alkanol to effect 2',3'- and 3',4'-epoxidation and concurrently removal of the 2'- and 2"-acyl groups, reducing the resultant N-protected 2',3'-anhydro-3'-epi derivative and 3',4'-anhydro-3'-epi derivative of kanamycin A either with hydrogen in the presence of a known hydrogenation catalyst or with sodium borohydride to afford the corresponding N-protected 3'-deoxygenated derivative of kanamycin A and then removing the residual amino-protecting groups therefrom to give 3'-deoxykanamycin A.

Abstract: New routes are provided for the synthesis of 3',4'-dideoxykanamycin B which is effective in inhibiting kanamycin-resistant organisms from kanamycin B through new intermediate, of which a fundamental process comprises a new reaction of a 3',4'-epoxy derivative of amino- and hydroxyl-protected kanamycin B with a xanthate to form a corresponding 3',4'-dideoxy-3'-eno derivative followed by removal of the amino- and hydroxyl-protecting groups thereof and by hydrogenation of the resulting 3',4'-dideoxy-3'-eno-kanamycin B. A 3',4'-episulfide derivative corresponding to the 3',4'-epoxy derivative which is formed as second product in the reaction of 3',4'-epoxy derivative with xanthate is also used as intermediate for the preparation of 3',4'-dideoxykanamycin B.

Abstract: 3'-Deoxykanamycin A useful as antibacterial agent is produced from a protected kanamycin A derivative either by a process comprising imidazolylthiocarbonylation of the 3'- and 2"-hydroxyl groups of 4",6"-O-cyclohexylidene-4'-0:6'-N-carbonyl-5,2'-O-isopropylidene-1,3,3"-tr i-N-tosylkanamycin A, preferential removal of the 3'-imidazolylthiocarbonyloxy group with tributyltin hydride for the 3'-deoxygenation, followed by removal of the 2"-O-imidazolylthiocarbonyl group with aqueous ammonia, removal of the N-tosyl groups with alkali or alkaline earth metal in liquid ammonia, hydrolytic fission of the 4',6'-cyclic carbamate ring and concurrent removal of the 5,2'-O-isopropylidene group and 4",6"-O-cyclohexylidene group, or by a process comprising selective acetylation of the 2"-hydroxyl group of said protected kanamycin A derivative with acetyl chloride in pyridine, trifluoromethanesulfonylation of the 3'-hydroxyl group, followed by concurrent removal of the 3'-trifluoromethanesulfonyloxy group and N-tosyl groups w

Abstract: 3'-Deoxykanamycin B, namely tobramycin is produced in an improved yield with a reduced reaction time under moderate reaction conditions, starting from a penta-N-protected 3'-mono-O-alkyl-, aralkyl- or arylsulfonylated derivative of kanamycin B in which all the 1, 3, 2' and 3"-amino groups and possibly the 6'-amino group have been protected by an arylsulfonyl group, especially tosyl group; the 3'-hydroxyl group of kanamycin B has been alkyl-, aralkyl- or arylsulfonylated; the 4"- and 6"-hydroxyl groups have been blocked with a di-valent hydroxyl-protecting group; and possibly the 4'-hydroxyl group and 6'-amino group have been blocked by being converted into the form of a 4', 6'-cyclic carbamate formed between the 4'-hydroxyl group and the 6'-amino group, by subjecting to a process essentially comprising reaction of said protected kanamycin B derivative with a metal halide for a reaction time of 30 min. to 2 hours at a reaction temperature of 0.degree. C..about.150.degree. C.

Abstract: There are provided new compounds, 3',4'-anhydro-4'-epi derivatives of kanamycin A of the formula: ##STR1## wherein R represents an alkyl, aralkyl or aryl group and Y represents an alkylidene, aralkylidene, cycloalkylidene or tetrahydropyranylidene group which are useful as an intermediate for the synthesis of 3',4'-dideoxykanamycin A and 4'-deoxykanamycin A from kanamycin A. The compounds of formula (I) can be prepared by treating the corresponding 4'-O-sulfonyl derivative with an alkali metal alcoholate in a lower alkanol under an alkaline condition.

Abstract: 3',4'-Dideoxy derivative and 1-N-((S)-.alpha.-hydroxy-.omega.-aminoalkanoyl)-3',4'-dideoxy derivative of kanamycin A are now synthetized from kanamycin A and show a wider and/or higher antibacterial activity than the parent kanamycin A so that they are useful in therapeutic treatment of infections by gram-negative and gram-positive bacteria, including drug-resistant strains thereof.

Abstract: Aminoglycosidic antibiotic comprising a 6-0-(3"-aminoglycosyl)-2-deoxystreptamine optionally having a 4-0-(aminogycosyl) group, such as kanamycins, gentamicins, sisomicin, forms reversible complex with zinc cations by association of the zinc cations with some pairs of aminohydroxyl groups in the aminoglycoside, and the zinc-complexed amino groups are blocked from acylation. Reaction of this zinc complex with an acylation reagent having an amino-blocking acyl group brings about acylation of the non-complexed amino groups to give an N-acylated zinc complex, namely a complex of zinc cation with an N-acylated aminoglycosidic antibiotic derivative. Removal of zinc cations from N-acylated zinc complex yields a partially N-acylated aminoglycosidic antibiotic where 1- and 3"-amino groups are unprotected but all other amino groups protected with acyl group.

Abstract: By protecting the aldehyde group of a macrolide series antibiotics with a cyclic acetal or thioacetal, novel macrolide derivatives can be produced from the macrolide series antibiotics by releasing successively, the sugar moieties bonded to the macrolide antibiotics.The novel marcolide derivatives obtained by this invention, that is, the derivatives of a macrolide series antibiotics produced by releasing partially or wholly the sugar moieties bonded are useful as intermediates for producing novel macrolide series antibiotics.

Abstract: By protecting the aldehyde group of a macrolide series antibiotics with a cyclic acetal or thioacetal, novel macrolide derivatives can be produced from the macrolide series antibiotics by releasing successively, the sugar moieties bonded to the macrolide antibiotics.The novel macrolide derivatives obtained by this invention, that is, the derivatives of a macrolide series antibiotics produced by releasing partially or wholly the sugar moieties bonded are useful as intermediates for producing novel macrolide series antibiotics.

Abstract: New routes are provided for the synthesis of 3',4'-dideoxykanamycin B which is effective in inhibiting kanamycin-resistant organisms from kanamycin B through new intermediate, of which a fundamental process comprises a new reaction of a 3',4'-epoxy derivative of amino- and hydroxyl-protected kanamycin B with a xanthate to form a corresponding 3',4'-dideoxy-3'-eno derivative followed by removal of the amino- and hydroxyl-protecting groups thereof and by hydrogenation of the resulting 3',4'-dideoxy-3'-eno-kanamycin B. A 3',4'-episulfide derivative corresponding to the 3',4'-epoxy derivative which is formed as second product in the reaction of 3',4'-epoxy derivative with xanthate is also used as intermediate for the preparation of 3',4'-dideoxykanamycin B.