11 результати
The antitumor effects of 6-O-(3-ethoxypropionyl)-3',4'-O-exo- benzylidenechartreusin (IST-622), a new synthetic derivative of chartreusin (CT), were investigated. Following oral administration, IST-622 showed marked antitumor effects against various mouse tumors such as P388 and L1210 leukemias, B16
Chartreusin and elsamicin A are structurally related antibiotics that bind to GC-rich tracts in DNA, with a clear preference for B-DNA over Z-DNA. They inhibit RNA synthesis and cause single-strand scission of DNA via the formation of free radicals. Elsamicin A can also be regarded as the most
In order to overcome the rapid biliary excretion of chartreusin, which diminished its activity when administered iv, a series of 3',4'-O-substituted derivatives of chartreusin were synthesized. Exo-type of 3',4'-O-benzylidene-chartreusin was found active both by ip and iv administration. Therefore,
Chartreusin has exhibited significant therapeutic activity against three experimental mouse tumors (ascitic P388, L1210 leukemia, and B16 melanoma) when tumor cells were inoculated i.p. and drug was administered i.p. In further testing against P388 leukemia, no activity was observed when drug was
New antitumor antibiotics, elsamicins A and B, were isolated from the culture broth of an unidentified actinomycete strain J907-21 (ATCC 39417). They are structurally related to chartreusin, containing the common aglycone, chartarin, but contain different sugar moieties. Elsamicin A, the major
Background
Endophyte has now become a potential source for the discovery of novel natural products, as they participate in biochemical pathways of their hosts and produce analogous or novel bioactive compounds. As an epiphytic plant,
Dendrobium officinale is one of
Natural products of the benzonaphthopyranone class, such as chartreusin, elsamicin A, gilvocarcin, and polycarcin, represent potent leads for urgently needed anticancer therapeutics and antibiotics. Since synthetic protocols for altering their architectures are limited, we harnessed enzymatic
Irinotecan hydrochloride (CPT-11), topotecan, sobuzoxane, NC-190, and IST-622 are unique topoisomerase inhibitors and are investigational in Japan. CPT-11 is a water-soluble, semisynthetic derivative of camtothecin. CPT-11 shows its anticancer activity by inhibiting topoisomerase I activity, now a
A new antitumor antibiotic, 3''-demethylchartreusin was isolated from the culture broth of Streptomyces chartreusis, as a minor component of crude chartreusin. It is structurally related to chartreusin, containing same aglycone of chartreusin, but different sugar moieties. 3''-Demethylchartreusin
In our laboratory, we have studied the mechanism of action of tumor-inhibitory antibiotics, including bleomycin, phleomycin, adriamycin, aclarubicin, neothramycin, macromomycin, auromomycin, chartreusin, pluramycin, neopluramycin, xanthomycin A, angustmycins A and C, blasticidin S and phenomycin.
The cytostatic agent Elsamitrucin is a new fermentation product active in a variety of in vivo tumor models of murine and human origin. To determine its pharmacokinetics during the clinical phase I trial, an HPLC procedure was developed and validated. Plasma samples were extracted after addition of