Anthraquinone antibiotics

In light of the growing problem of multidrug resistance in malaria parasites in the 1970s, several well known anthraquinone antibiotics... 

The addition-protonation procedure maintains the arene-chromium bond and allows further application of the activating effect of the metal. In an approach to the synthesis of anthraquinone antibiotics, the dihydronaphthalene complex (79) was allowed to react with a cyanohydrin acetal anion and then quenched with acid.129 The resulting tetralin complex (80) could be metallated effectively and carried on to a key intermediate (81) in anthraquinone construction (equation 54)... 

Several synthetic compounds containing the naphthoquinone skeleton, such as 2-(4-cyclohexylcyclohexyl)-3-hydroxy- 1,4-naphthoquinone [169], are effective in the treatment of coccidial infection. Two structurally related antibiotics WS-5995A (36) and WS-5995B (37a), isolated from S. auranticolor sp. nov. near Tokyo, efficiently protect Eimeria tenella (a species of coccidia) infection. An inactive component WS-5995C (37b) can be readily converted to the active (36) by simple dehydration [ 170-172]. Compound (36), the structure of which resembles the aforementioned benz[a]anthraquinone antibiotics, is the first example of a 5//-benzo[d ]naphtho[ 2,3-6 ]pyran ring system found in nature. 

Phthalides are valuable synthons for obtaining several biologically active compounds and natural products. Naphthols, anthraquinones and anthraquinone antibiotics, isoquinolones, phthalide isoquinolines, indolizidine and quinolizidine alkaloids, and berbine alkaloids have been synthesised with phthalides as the starting compounds. Some of the syntheses, which have interesting chemistry, are described below. The required phthalides, in some cases, have been synthesised through aromatic lithiation reactions, while in others by more conventional methods. 

In 1982, Omura etal. reported the isolation of a new diaza-anthraquinone antibiotic called OM-704 [30), which was later characterized as diazaquinomycin A (62) [31), from a fermentation broth of a Streptomyces sp. OM-704, a solid isolate. The isolation of diazaquinomycin B (63) was reported during the characterization of diazaquinomycin A as a minor product of the fermentation [31). 

The DNA photocleaving abiUties of these hybrids were much higher than that of the natural anthraquinone antibiotic, daimomycin (lanes a and b vs lane d in Fig. 8). These results demonstrate that artificial anthraquinone-carbohydrate hybrids are superior to this natural anthraquinone product as a DNA photocleaving agent. 

For the purification of hydrophobic anthraquinone antibiotics, such as elloramycin (structure in Figure 10.1), the influence of particle size of the C-18 stationary phase on the purification efficiency has been studied. The separation resolution, product purity, and recovery were compared with use of lOpm and 15-25pm Nucleosil C-18 column. Tlie results shown in Table 10.2 demonstrate that with small and homogeneous particles used as the stationary phase, the separation resolution and product purity increases dramatically, though the recovery is not significantly affected. 

Anthraquinone antibiotic. Prod, by actinomycete AB 1246E-26. Active against gram-positive bacteria and tumours. 

Anthraquinone antibiotic. Constit. of Pe-nicillium nigricans. Cryst. 

C49H58O18 934.986 Anthraquinone antibiotic. Prod, by Streptomyces malensis. Active against gram-positive bacteria, sarcoma cells and tumours. Yellow amorph. powder. Sol. MeOH, CftHs poorly sol. H2O, hexane. 

Anthraquinone, 1-hydroxy-calcium aluminum chelate compound, 1,2 metal complexes dyes, 6,86 Antiarthritis drugs labelled gold compounds, 6, 969 metal complexes, 6,758 Antibiotic M139163,2, 974 Antibiotics ionophoric, 6, 553 metal complexes selective binding, 6, 552... 

Danishefsky et al. succeeded in preparing the benz[a] anthracene core structure 111 of angucycline antibiotics by performing a benzannulation reaction with the cycloalkynone 109 [69]. Deprotonation of the naphthoquinone 110 with DBU yields the desired anthraquinone 111 (Scheme 49). 

Much toxicological data are available on this red pigment acute oral toxicity in mice, 90-day subchronic toxicological study, acute dermal irritation and corrosion, acute eye irritation and corrosion, anti-tumor effectiveness, micronucleus test in mice, AMES test Salmonella typhimurium reverse mutation assay), estimation of antibiotic activity, and results of estimation of five mycotoxins. A new patent on Arpink Red was filed in 2001 with claims of anti-cancer effects of the anthraquinone derivatives and apphcations in the food and pharmaceutical fields. 

A synthesis of the chlorinated angucycline antibiotic BE-23254 (1686), which was isolated from Streptomyces sp. A 23254, has confirmed the structure of this benz[a anthraquinone derivative (1644,1939,1940). Two detailed examinations of the rare Australian soil actinomycete Kibdelosporangium sp. uncovered a series of... 

Among all the isotetracene antibiotics, tetrangomycin (32a), obtained from S. rimosus, possesses the simplest structure, and is the first antibiotic to be isolated [162, 163]. Compound (32a) differs from (31) only by the presence of a double bond (instead of a diol) between C-4a and C-12b. Base treatment of (32a) does not cause a skeletal rearrangement, but readily aromatizes it to the benz[a]anthraquinone derivative, tetrangulol (33a). The latter is an antibiotic per se, since it can also be isolated from the culture filtrates of S. rimosus without any alkaline treatment [162]. A related antibiotic rabelomycin (32b)... 

Included in such compounds are the fatty acids, polyacetylenes, prostaglandins, macrolide antibiotics and many aromatic compounds, e.g. anthraquinones and tetracyclines. 

Heterocyclic analogues of anthraquinone are a family of potent antibiotics, many with antitumor and cytostatic properties. Diazaquinomycin A (118) is a thymidine synthetase inhibitor <88TL3545>. Low solubility of compound (118) has led to the development of more soluble active analogues, for example, (119) (92JPS815, 94EUP574195). 

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