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T Niida

Publications and source records attributed to T Niida.

At least 37 records · Page 2Linked to original sources
PubMed1981

Studies on a new aminoglycoside antibiotic, dactimicin. II. Isolation, structure and chemical degradation.

A new aminoglycoside antibiotic, dactimicin produced by a Dactylosporangium matsuzakiense SF-2052 has been isolated by column chromatography on a cation-exchange resin and CM-sephadex. The structure of dactimicin was determined to be 4-amino-1,4-dideoxy-3-O-(2,6-diamino-2,3,4,6,7-pentadeoxy-beta-L-lyxo- heptopyranosyl)-1-[(N-formimidoylglycyl)-methylamino]-6-O-methyl-L-chiro-inosit ol. Alkaline hydrolysis of dactimicin afforded 1-N-(N-formylglycyl)fortimicin B, fortimicin B, fortimicin A and an acyl migration product, 2'-N-(N-formylglycyl)fortimicin B.

Aminoglycosides↗
PubMed1980

SF-1771, a new antibiotic related to bleomycin.

A new antibiotic, substance SF-1771, has been isolated for the fermentation broth of Streptomyces toyocaensis SF-1771. The antibiotic is highly active against Gram-positive and -negative bacteria and effective against sarcoma 180 cells of ascites type in mice. It belonged to the phleomycin-bleomycin group antibiotics, but has been differentiated from the known antibiotics by the physiochemical properties, chromatographic behaviors and amino acid analysis.

Animals↗
PubMed1980

gamma-Chloronorvaline, a leucine analog from Streptomyces.

gamma-Chloronorvaline (AL-719) and gamma-hydroxynorvalinelactone (AL-719Y) were isolated from the culture broth of Streptomyces griseosporeus AL-719. Physico-chemical studies led to the structure elucidation of AL-719 and 719Y, with there respective configurations of (2S, 4S) and (2S, 4R). AL-719 shows antibacterial activity on a synthetic agar, especially against Pseudomonas aeruginosa, which was reversed by L-leucine. The producing strain AL-719 was characterized.

Anti-Bacterial Agents↗
PubMed1980

Modifications of a macrolide antibiotic midecamycin. II. Reaction of midecamycin and 9-acetylmidecamycin with dimethylsulfoxide and acetic anhydride.

Treatment of 9,2'-diacetylmidecamycin (2) with DMSO and acetic anhydride afforded 3''-methylthiomethyl derivative (3) preferably in the presence of pyridine. Reaction of midecamycin (1) with DMSO and acetic anhydride gave 2'-acetyl-9-dehydro-3''-methylthiomethyl derivative (9) indicating that the three hydroxyl groups reacted in a different way to the reagent. When compound 2 was reacted with DMSO and acetic anhydride in the presence of CCl4, 3''-acetoxymethyl derivative (13) was a major product, which was formed via 3 through the Pummerer rearrangement. The structures of 3, 9 and 13 were confirmed by examining NMR and mass spectra of these compounds and their deuterio analogue. They showed antimicrobial spectra similar to 1 but superior in vivo activity.

Acetic Anhydrides↗
PubMed1980

Studies on a new aminoglycoside antibiotic, dactimicin. I. Producing organism and fermentation.

The producing organism of a new antibiotic, dactimicin, is described. The presence of finger-shaped sporangia bearing motile spores, the absence of aerial mycelium and its cell wall of type II, ascribe this organism to the genus Dactylosporangium. The cultural and physiological features distinguish this organism from all the described Dactylosporangium species. Therefore, it is considered to be a new species for which the name Dactylosporangium matsuzakiense sp. nov. is proposed. Fermentation of dactimicin is also described.

Aminoglycosides↗
PubMed1979

Studies on Actinomycetales producing antibiotics only on agar culture. I. Screening, taxonomy and morphology-productivity relationship of Streptomyces halstedii, strain SF-1993.

Soil Actinomycetales that produce antibiotics during growth on agar but not in submerged culture were searched for and about 25 strains were obtained. One of these, Streptomyces halstedii, strain SF-1993, which produces an antibiotic designated SF-1993 was studied taxonomically and morphologically. The antibiotic-productivity of strain SF-1993 was correlated with mycelial morphology. The vegetative mycelium was filamentous in antibiotic-producing agar cultures, but fragmented in non-producing submerged cultures. By maintaining submerged cells filamentous, production of antibiotic in the submerged fermentations was accomplished. Filamentation was maintained by the use of diluted media or non-fragmented mutant substrains.

Agar↗
PubMed1976

Modifications of a macrolide antibiotic midecamycin (SF-837). I. Synthesis and structure of 9,3''-diacetylmidecamycin.

9,3''-Diacetylmidecamycin (12) was synthesized from 4''-depropionyl-9,2',4''-triacetylmidecamycin (8) by heating the latter with propionic anhydride in pyridine followed by removal of 2'-acetyl group, with or without 18-enolpropionyl group. Direct acetylation of midecamycin (1) led to the formation of the 3'',4''-positional isomer (6). The structure of 12 was determined by mass, NMR and chemical degradation. The location of 3''-acetyl group was shown by the stereospecific 3 leads to 1 acetyl migration catalyzed by a base of 3-O-acetyl-4-O-propionyl-L-mycarose (13), and comparison of NMR and mass fragmentation with the 3,4-positional isomer (15). The latter's structure was independently supported by the nuclear Overhauser effect between methyl and propionyl group at C-3. The intramolecular 4 leads to 3 acyl shift that was taken place in the forced acylation of the mycarose moiety was found to be affected by the anomeric configuration, nature of aglycones and reaction temperature. Reverse 3 leads to 4 acyl migration occurred in acidic hydrolysis.

Acetylation↗
PubMed1976

Protective effect of D-glucaro-delta-lactam against amino-glycoside-induced nephrotoxicity in rats.

The nephrotoxicity of rats caused by dibekacin (3',4'-dideoxykanamycin B) or kanamycin with or without dextran was effectively reduced by D-glucaro-delta-lactam potassium salt, as evidenced by lower levels of blood urea nitrogen and kidney edema rate, better excretion of antibiotics,and less morphological damage. Protection was dosage related, and potentiated with increasing doses, but only when the two drugs were given simultaneously. Among three alkali-metal salts examined, the potassium salt was almost equal to the lithium salt, but surpassed the sodium salt in effectiveness. Inorganic salts, in particular potassium chloride were found to be effective for the protection of normal rats, but their effect decreased for the dehydrated rats, especially in the presence of dextran.

Aminoglycosides↗