Actinomycinic acid

For the synthesis of the heterodet cyclic depsipeptides, the acid chloride which had been prepared after the removal of the iV-protecting groups was most used. Recently, a mixture of acetylchlqride and acetylimidazole has been used for the cyclization of actinomycin acid to actinomycin Ci . Heterocyclic peptides containing disulphide rings have been cyclized by oxidation of the corresponding disulphydryl compounds . 

Actinomycin, no movement actinomycinic acid, high mobility towards cathode actinomycin monolactone, one-half mobility of the di-acid Ref... 

Those herbicides that block mitotic entry decrease or prevent the formation of mitotic figures in meristems. Amino acid, protein, RNA, DNA, and ATP synthesis and/or utilization can all attest cell growth (163,166). Although not registered as herbicides, cycloheximide [66-81-9] inhibits mitotic entry by inhibiting protein synthesis (167) hydroxyurea/727-(97-/7 inhibits DNA synthesis (168) and actinomycin D [50-76-0] nh2oix.s RNA synthesis (167). 

Almost all actinomycins have the same chromophore, a planar phenoxa2inone dicarboxyUc acid called actinocin. In dactinomycin, the stmcture of which is shown in Figure 12, the two pendent pentapeptide lactones are identical, but in other actinomycins these lactones may be different. In other actinomycins the first amino acid, amide linked with actinocin, is usually L-threonine, as in dactinomycin the second position is sometimes D-aHo-isoleucine instead of D-valine the third position may be sarcosine or oxoproline the fourth position is sarcosine and the fifth position is sometimes /V-methyl isoleucine instead of /V-methylvaline. The lactone ring is always present. 

Actinocin — see Phenoxazine-l,9-dicarboxylic acid, 2-amino-4,6-dimethyl-3-oxo-Actinoleutin applications, 3, 195 Actinomycins... 

The NMR experiments 55 are obtained from actinomycin D in order to check the amino acid sequence, to assign proton-proton and some carbon-proton connectivities, and to deduce informations concerning proton distances and the spatial structure of both cyclopentapeptide lactone rings. Conditions CDCI3, 10 mg per 0.3 ml, 25 °C, 500 MHz H), 125 MHz ( C). (a) HH COSY plot ... 

One of the key steps in the synthesis of actinomycin D (241 Scheme 3.88) and its serine analogue involved the regio- and stereoselective ring-opening of aziridine 238 with the acid 239 [138, 139]. This transformation took place in methylene... 

Phenoxazines — The microbial phenoxazines like actinomycins are well-known antibiotics. Actinomycin D produced by Streptomyces anibioticus is an effective antineoplastic agent that inhibits nucleic acid synthesis. The main function of ommochromes is to act as screening pigments in the eyes of insects and other arthropods, as pattern pigments in the integument, and as excretion products of excess tryptophan. ... 

Sobell, H. M. The Stereochemistry of Actinomycin Binding to DNA and its Implications in Molecular Biology in Progress in Nucleic Acid Research and Molecular Biology (Davidson, J. N Cohn, W. E., eds.), Academic Press, New York 1973, p. 153... 

This increase in enzyme activity can be prevented by the administration of actinomycin D [133] or an androgen such as testosterone propionate [134]. Pretreatment of partially hepatectomized rats with methotrexate markedly decreases the incorporation of orotic acid into DNA of the regenerating livers... 

The use of antibiotics for the control of plant virus diseases( ) is of interest. Several antibiotics have been tested for inhibition of replication of viral nucleic acid and/or protein synthesis within the host cell. Chloramphenicol, cycloheximide, actinomycin D and others are the most used antibiotics and the disease caused by tobacco mosaic... 

The induction of PAL activity at the onset of vascular differentiation can be shown by the use of plant tissue cultures (37-39). Xylem cells with secondary and lignified walls are differentiated over a time course of 3-14 days by the application of the plant growth factors naphthylene acetic acid (NAA) and kinetin in the ratio 5 1 (1.0 mg/liter NAA, 0.2 mg/liter kinetin) to tissue cultures of bean cells (Phaseolus vulgaris) (37,40). The time for differentiation varies with the type of culture, solid or suspension, and with the frequency and duration of subculture, but for any one culture it is relatively constant (37,41,42). At the time of differentiation when the xylem vessels form, the activity of PAL rises to a maximum. The rising phase of the enzyme activity was inhibited by actinomycin D and by D-2,4-(4-methyl-2,6-dinitroanilino)-N-methylpropionamide (MDMP) applied under carefully controlled conditions (42). This indicated that both transcription and translation were necessary for the response to the hormones. Experiments using an antibody for PAL and a cDNA probe for the PAL-mRNA have also shown that there is an increase in the amount of transcript for PAL during the formation of lignin when Zinnia mesophyll cells are induced to form xylem elements in culture (Lin and Northcote, unpublished work). 

Acid DNase is strongly inhibited by actinomycin D. In contrast with the claim (44) that actinomycin causes the same extent of inhibition of... 

Morphological changes were prevented in butyrate-treated HeLa cells by actinomycin D and cycloheximide (2,8,13). After removal of butyrate, the cells reverted to a normal morphology over a 24 h time course (2,8,12,13). When butyrate-treated cells were detached from the cuTture dishes with trypsin, they assumed a spherical shape and, when replated in the absence of butyrate, their neurite-like processes transiently re-extended (13). This re-extension was blocked when cycloheximide but not the calcium ionophore was included during the initial exposure of the cells to butyrate (13). Process formation, however, did resume in the presence of cycloheximide (1 3). These results were interpreted as indicating that the fatty acid induces a protein(s) required for process formation which can accumulate in the absence of processing and promote processing in the absence of inducer (13). 

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