1.4- Dihydroxy-6-methylanthraquinone

Dihydroxy-3-methylanthraquinone (chrysophanic acid) [481-74-3] M 245.3, m 196 , PKesi(I) 8.2, pKest(2) 12.4. Crystd from EtOH or benzene and sublimed in a vacuum. 

In similar experiments, cell-free preparations of a Streptomyces coelicolor strain containing the minimal PKS involved in actinorhodin biosynthesis were shown to produce compounds called SEK4 and SEK4b, molecules generated as shunt products of the normal pathway (Fig. 7). When the strain also included genes for the KR, ARO, and CYC activities, a more elaborate structure, 3,8-dihydroxy-l-methylanthraquinone-2-carboxylic acid (DMAC), was obtained (Fig. 7) [8], Biosynthesis of SEK4 and SEK4b has also been accomplished in... 

Constituents (See also table HI) Approx. 0,4% of hydroxyanthra-quinones the principal components are Morindon (XXIII) and Morindin (morindon-5-rutinoside). Other constituents are soranjidiol (XIV), morindadiol (1,5-dihydroxy-2(or 3)-methylanthraquinone), rubiadin... 

A-Dihydroxy-2-hydroxy-methylanthraquinone (XI) Quinizarin-2-carboxylic acid (XII)... 

The activity of the complete act PKS has also been demonstrated. Extracts containing the act KR, CYC and ARO in addition to those of the minimal PKS catalyzed the synthesis of 3,8-dihydroxy-l-methylanthraquinone-2-carboxylic acid (DMAC), the primary in vivo product of the complete act PKS. The structure of this product was verified by its enzymatic conversion into 8-methoxy DMAC by the tcmO 0-methyltransferase, which was prepared from a separate strain which expressed this protein (Fig. 4). 

DIhydroxy>3-methylanthraquinone, Chrysophanic Acid, Methylchrysazin, Chrysophanol (called 4,5-Dioxy-2-methyl-anthrachinon 3 Methyl chrysazin Chryso phanoi or Chrysophansaure in Ger),... 

Natural quinones also exert antiviral activity against other viruses, such as the Epstein-Barr virus and poliovirus type 2 and 3 [163-165], For example, chrysophanic acid (l,8-dihydroxy-3-methylanthraquinone) isolated from the Australian Aboriginal medicinal plant Dianella longifolia Street has been found to inhibit the replication of poliovirus type 2 and 3 in vitro. Four structurally-related anthraquinones (rhein, Fig. (5), 1,8-... 

Methyl ether, Cl6H,205, lf8 dihydroxy 3-methoxy 6 methylanthraquinone, rheochrysidin. Brick-red, monoclinic needles, mp 207. Occurs naturally as physcione or parietin. 

Rubiadin. 1,3-Dthydroxy-2-methyl-9,I0-anthra-unedume l,3-dihydroxy-2-methylanthraquinone. C,sH10Ot mol wt 254.23. C 70.86%, H 3.96%. O 25.17%. From Rubio linciorum L Coprosma var, Morinda citrifolia Linn, Rubia-ceae Schunck, Ann. 87, 344 (1853) Briggs, Nicholls, J. 

Physcion (parietin, l,8-dihydroxy-3-methoxy-6-methylanthraquinone, emodin 3-0-methyl ether). 

Dihydroxy-3-methylanthraquinone 4,5-Dlhydroxy-2-methylanthraquinone 3-Methylchrysazin 2-Methyl-4,5-dihydroxyanthraquinone 3-Methyl-1,8-dihydroxyanthraquinone Rhenic acid Turkey rhubarb... 

Dihydroxy-3-methylanthraquinone 4,5-Dihydroxy-2-methylanthraquinone. See Chrysophanic acid... 

Intact plants and cell cultures of Streptocarpus dunnii (Gesneriaceae) contain several 1,2-naphthoquinones with a reversed prenyl side chain, such as that in dunnione (66) (Fig. 6.16), l-Hydroxy-2-methylanthraquinone (67) and 1-hydroxy-2-(hydroxymethyl)anthraquinone (68) were also isolated from this culture. Administration of [1-carboxy- C]<9-succinylbenzoate revealed that was incorporated into the 1-position of dunnione and the 10-position of anthraquinones. These results, together with those of feeding experiments in which lawsone (41) and its 2-prenyl ether (69) were applied, suggested that dunnione (66) was formed by a Claisen-type rearrangement at the 2-position of 2-carboxy-4-oxotetralone (COT) (43), whereas anthraquinones were formed by prenylation at the 2-position of 2-carboxy-4-oxo-tetralone (COT) (43) or l,4-dihydroxy-2-naphthoic acid (40) (Inouye and Leistner, 1988). 

Me ether [155587-33-0]. l-Chloro-2,4-dihydroxy-5-methoxy-7-methylanthraquinone Ci HjiClOs M 318.713... 

Tri-Me ether [157556-87-1]. 5,8-Dihydroxy-1,2J-trimethoxy-7-methylanthraquinone CigHi O M 344.320 Constit. of the stem bark of Cassia javanica (Leguminosae). 

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