Abstract: The present high-frequency distribution circuit includes a switch circuit which passes a high-frequency signal from the other terminal of a high-frequency line to an output terminal if a receiver is connected to the output terminal and which grounds the other terminal of the high-frequency line via a terminator resistor if the receiver is not connected to the output terminal. As seen at an input terminal toward the output terminal, a constant value in resistance is provided regardless of whether the output terminal is used or not.

Abstract: The present high-frequency distribution circuit includes a switch circuit which passes a high-frequency signal from the other terminal of a high-frequency line to an output terminal if a receiver is connected to the output terminal and which grounds the other terminal of the high-frequency line via a terminator resistor if the receiver is not connected to the output terminal. As seen at an input terminal toward the output terminal, a constant value in resistance is provided regardless of whether the output terminal is used or not.

Abstract: Neplanocin A derivatives of the formula ##STR1## wherein R.sub.1 is hydrogen or benzoyl, R.sub.4 is hydrogen or halogen, hydroxy, acetoxy, acetylthio, amino or azide, R.sub.5 is hydrogen or acetyl, and R.sub.6 is hydrogen or acetyl. The compounds of the present invention have inhibitory action for the growth of L 5178 Y cells and have the same or superior activity as neplanocin A.

Abstract: Compounds of the formula ##STR1## wherein R.sub.1 is lower alkyl, lower alkoxycarbonyl-lower alkyl, phenyl, phenyl substituted by one or more lower alkyl or halogen, phenyl-lower alkyl optionally substituted in its side chain by lower alkyl or lower alkoxycarbonyl, thienylmethyl or thiazolyl, R.sub.2 is hydrogen or lower alkyl, or ##STR2## constitutes a 3-7-membered nitrogen-containing heterocyclic ring in which R.sub.1 and R.sub.2 are connected, R.sub.3 is hydrogen or hydroxyl, and X is oxygen or sulfur, or a non-toxic salt thereof. These compounds have stronger antibacterial activity as compared with known clinically used macrolide antibiotics such as erythromycin, oleandomycin, josamycin and leucomycin, and also have strong antibacterial activity against all macrolide antibiotic-resistant strains such as macrolide-resistant A group strains (clinical isolates or erythromycin, oleandomycin and 16-membered macrolide antibiotic resistant strains).

Abstract: Novel 3-O-acyl-4"-deoxydesmycosin derivatives of the formula ##STR1## wherein R.sub.1 is lower alkyl, phenyl, substituted phenyl, phenyl-lower alkyl or substituted phenyl-lower alkyl, R.sub.2 is hydrogen or --CHO and R.sub.3 is hydrogen or hydroxyl, or a non-toxic salt thereof, can be produced by acylating the hydroxyl group at position-3 of the corresponding intermediate while protecting the hydroxyl at position-2' or positions-2' and -4' with acetyl, and then removing the protective group or groups. These derivatives have antibiotic utility against Gram positive and Gram negative bacteria.

Abstract: Neplanocin A derivatives of the formula ##STR1## wherein R.sub.1 and R.sub.2 are hydrogen or benzoyl, R.sub.3 is hydrogen or OR.sub.8, R.sub.5 is hydrogen or acetyl, R.sub.6 is hydrogen, acetyl or benzoyl, when R.sub.3 is hydrogen, R.sub.4 is hydrogen or halogen, hydroxy, acetoxy, acetylthio, amino or azide, and when R.sub.3 is OR.sub.8, R.sub.4 is hydrogen, R.sub.8 is hydrogen or acetyl, or R.sub.8 and R.sub.5 together form benzylidene, and at least one of R.sub.8, R.sub.5 and R.sub.6 is other than hydrogen. The compounds of the present invention have inhibitory action for the growth of L 5178 Y cells and have the same or superior activity as neplanocin A, and hence are useful as antitumor agents.

Abstract: A compound of the formula ##STR1## wherein R.sub.1 is hydrogen, --COOR.sub.11 or ##STR2## R.sub.11 is optionally substituted lower alkyl, R.sub.12 is optionally substituted hydrocarbon, heterocyclic or heterocyclic-lower alkyl, R.sub.13 is hydrogen or lower alkyl, or R.sub.12 and R.sub.13 together constitute a heterocyclic ring together with the attached nitrogen atom, and R.sub.2 is hydrogen or hydroxyl, or a pharmaceutically-acceptable salt thereof, has stronger antibacterial activity against Gram-positive bacteria than does tylosin. It is produced by deformylation, or by oxidizing a formyl at position-14, or by amidating the latter compound.

Abstract: Novel 23-demycinosyldesmycosin derivatives are disclosed of the formula ##STR1## wherein A is oxygen or sulfur, R.sub.1 is optionally substituted phenyl or ##STR2## group, in which R.sub.3 is optionally substituted phenyl and R.sub.4 and R.sub.5 are the same or different and are hydrogen, lower alkyl or optionally substituted phenyl, and R.sub.2 is hydrogen or hydroxyl. The compounds or non-toxic salts thereof are useful as antibiotics.

Abstract: Compounds of the formula ##STR1## wherein R.sub.1 is optionally substituted phenyl, thienyl, 2-amino-4-thiazolyl or 2-chloroacetamido-4-thiazolyl; A is lower alkylene, lower alkenylene, or lower alkylene substituted by lower alkyl, amino, lower alkoxyimino or phenyl-Z-group wherein Z is a single bond or --S-- or --SO.sub.2 --, but when R.sub.1 is 2-amino-4-thiazolyl or 2-chloroacetamido-4-thiazolyl then A is lower alkylene substituted by lower alkoxyimino; R.sub.2 is hydrogen or hydroxyl; X is oxygen or sulfur and n=0 or 1, or a non-toxic salt thereof. These compounds have a stronger antibacterial activity against Gram positive bacteria as compared with known macrolide antibiotics such as erythromycin and tylosin, and also have an equivalent level of antibacterial activity against Gram negative bacteria as compared with that of erythromycin, and hence may be useful for clinical use. These compounds are also useful for feed additives and growth stimulants.

Abstract: A compound of the formula ##STR1## wherein R.sub.1 and R.sub.2 are hydrogen or hydroxy and at least one of R.sub.1 and R.sub.2 is hydrogen, or a pharmaceutically acceptable salt thereof, has strong antimicrobial and antibacterial activity..

Abstract: A compound of the formula ##STR1## wherein R.sub.1 and R.sub.2 are hydrogen or hydroxyl and at least one of R.sub.1 and R.sub.2 is hydrogen, or a pharmaceutically acceptable salt thereof, has antibacterial activity against Gram positive bacteria and against macrolide-resistant A group bacteria.