Results 131 to 140 of about 118,548,268 (167)

Enhanced production of validamycin A in Streptomyces hygroscopicus 5008 by engineering validamycin biosynthetic gene cluster

Applied Microbiology and Biotechnology, 2014
Validamycin A (VAL-A) is a widely used antifungal antibiotic for the treatment of sheath blight disease of rice and other plants. It can be produced from agro-industrial by-products by Streptomyces hygroscopicus 5008. To enhance its production titer, in this work, the entire val gene cluster was amplified in tandem in S.
Tan-Che, Zhou, Byung-Gee, Kim, Jian-Jiang, Zhong   +2 more
openaire   +2 more sources

ChemInform Abstract: Synthetic Studies on Antibiotic Validamycins. Part ll. Synthesis of Validamycin A.

Chemischer Informationsdienst, 1986
AbstractValidoxylamin A (Ia), das Aglycon des Antibioticums Validamycin (A) (IIId), wird über die Stufen (Ib)‐(Id) in das Derivat (Ie) übergeführt, das durch Glykosylierung mit der Halogenose (II) das (IIId)‐Derivat (IIIa) liefert.
S. OGAWA, T. NOSE, T. OGAWA, T. TOYOKUNI, Y. IWASAWA, T. SUAMI   +5 more
openaire   +1 more source

A FORMAL TOTAL SYNTHESIS OF VALIDAMYCIN A

Chemistry Letters, 1983
Abstract Validamycin A has been prepared by a glycosidation of the partly blocked validoxylamine A, followed by deprotection. Since a racemic form of validoxylamine A has been totally synthesized, the synthesis of validamycin A is achieved by the present study.
Seiichiro Ogawa, Takao Ogawa, Taisuke Nose, Tatsushi Toyokuni, Yoshikazu Iwasawa, Tetsuo Suami   +5 more
openaire   +1 more source

ChemInform Abstract: Antibiotic Validamycins. Part 13. Total Synthesis of (+)‐Validamycins A and E, and Related Compounds.

ChemInform, 1989
AbstractAcetylated validamycins A (Xa) and E (Xb) are synthesized starting from the validoxylamine B derivative (I) via glycosylation of the intermediate (VI).
Y. MIYAMOTO, S. OGAWA
openaire   +1 more source

Synthetic studies on antibiotic validamycins. Part 14. Total synthesis of (+)-validamycins C, D and F

Journal of the Chemical Society, Perkin Transactions 1, 1991
(+)-Validamycins C and F were first completely synthesised by use of a common blocked derivative 5 of (+)-validoxylamine A. The diols 6 and 7, obtained by acid hydrolysis of 5, were appropriately protected to give the aglycones 17, 25 and 30, which were condensed with glycosyl donor 11 or 19 to afford the condensates 20 and 26, being convertible, by ...
Yasunobu Miyamoto, Seiichiro Ogawa
openaire   +1 more source

Synthetic studies on antibiotic validamycins. Part 12. Total synthesis of (+)-validamycin B and (+)-validoxylamine B

Journal of the Chemical Society, Perkin Transactions 1, 1988
The first complete synthesis of validamycin B (1a) and validoxylamine B (2a) is reported; coupling of the epoxide (12) and the partially protected derivative (16) of (+)-valienamine, followed by deprotection, gives (1a), which was identified from the 1H n.m.r. spectrum of its totally O-acetylated derivative (1b). Alternatively, coupling of the epoxide (
Seiichiro Ogawa, Yasunobu Miyamoto, Taisuke Nose   +2 more
openaire   +1 more source

Synthetic studies on antibiotic validamycins. Part 13. Total synthesis of (+)-validamycins A and E, and related compounds

Journal of the Chemical Society, Perkin Transactions 1, 1989
(+)-Validoxylamine A (1) has been completely synthesized by deoxygenation of the validoxylamine B derivative (6) through formation of the aziridine, nucleophilic displacement with toluenethiol, reduction with Raney nickel, and deprotection. The validoxylamine A derivative (10) obtained was convertible, by glycosylation followed by deprotection, into ...
Yasunobu Miyamoto, Seiichiro Ogawa
openaire   +1 more source

ChemInform Abstract: Synthetic Studies on Antibiotic Validamycins. Part 14. Total Synthesis of (+)‐Validamycins C, D and F.

ChemInform, 1991
AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Y. MIYAMOTO, S. OGAWA
openaire   +1 more source

ChemInform Abstract: Synthetic Studies on Antibiotic Validamycins. Part 12. Total Synthesis of (+)‐Validamycin B and (+)‐Validoxylamine B.

ChemInform, 1989
AbstractCoupling of the synthons (VI) and (VII) and subsequent work‐up leads to (+)‐validamycin B (IX).
S. OGAWA, Y. MIYAMOTO, T. NOSE
openaire   +1 more source

Validamycin Treatment Significantly Inhibits the Glycometabolism and Chitin Synthesis in the Common Cutworm, Spodoptera litura

Insect Science, 2022
Ming-Jie Deng, Zhan-Jun Lu, Hai-Zhong Yu
exaly