3 ,4 -Dihydroxy-2-methyl

Morinda citrifolia L. M. officinalis L. Je Shu Ba Ji Tian (root) Dihydroxy methyl anthraquinone, glucoside morindin, rubichloric acid, alizarin, alpha-methyl ether, rubiadin-I-methyl ether, tannins, morindadiol, masperuloside, soranjudiol, nordamnacanthal.50-424 Treat beri-beri, cancer, lumbago, cholecystitis, increase leukocyte count, stimulate endocrine system. 

An interesting experimental result was observed in the study of the mild acid hydrolysis of the cis and the trans bicyclic orthoesters 87 and 88 (60). The cis orthoester 87 gave under kinetically controlled conditions the dihydroxy methyl ester 89 whereas the trans orthoester 88 produced directly the hydroxy-lactone 90 under the same experimental conditions. These results can be explained on the basis of the principle of stereoelectronic control. 

The cis bicyclic orthoester 87 can exist in the two different conformations 91 and 92. The conformation 92 corresponds to that of the unreactive tricyclic orthoester 62, i. e. conformer it can therefore be eliminated. Con-former 91 can undergo the cleavage of the axial C —0 bond with stereoelectronic control to produce the lactonium ion 93 which after hydration will give the hemi-orthoester 94. Since the chair inversion in 94 is not favored because the hydroxyalkyl side chain would have to take the axial orientation, it is expected that 94 would give the dihydroxy methyl ester 89 preferentially. 

Synonyms Germall 77 N-(hydroxymethyl)-N-(l,3-dihydroxy-methyl-2,5-dioxo-4-imidazolidinyl)-N -(hydroxymethyl) urea. 

The 9 — 15 fragment was prepared by a similar route. Once again Sharpless kinetic resolution method was applied, but in the opposite sense, i.e., at 29% conversion a mixture of the racemic olefin educt with the virtually pure epoxide stereoisomer was obtained. On acid-catalysed epoxide opening and lactonization the stereocentre C-12 was inverted, and the pure dihydroxy lactone was isolated. This was methylated, protected as the acetonide, reduced to the lactol, protected by Wittig olefination and silylation, and finally ozonolysed to give the desired aldehyde. 

Diazo coupling involves the N exocyclic atom of the diazonium salt, which acts as an electrophilic center. The diazonium salts of thiazoles couple with a-naphthol (605). 2-nitroresorcinol (606), pyrocatechol (607-609), 2.6-dihydroxy 4-methyl-5-cyanopyridine (610). and other heteroaromatic compounds (404. 611) (Scheme 188). The rates of coupling between 2-diazothicizolium salts and 2-naphthol-3.6-disulfonic acid were measured spectrophotometrically and found to be slower than that of 2-diazopyridinium salts but faster than that of benzene diazonium salts (561 i. The bis-diazonium salt of bis(2-amino-4-methylthiazole) couples with /3-naphthol to give 333 (Scheme 189) (612). The products obtained from the diazo coupling are usuallv highly colored (234. 338. 339. 613-616). 

Rosolic acid, aurin, corallin, corallinphthalein, 4,4 -dihydroxy-fuchsone, 4,4 -dihydroxy-3-methyl-fuchsone (indicator) dissolve 0.5 g in 50 mL alcohol and dilute with water to 100 mL. Salicyl yellow (indicator) see alizarin yellow GG. 

Fluoro-llb,21-dihydroxy-16a-methyl-21-(phosphonooxy)-pregna-l,4-diene- 3,20-dione, disodium salt. See Dexamethasone sodium phospate. 

Misoprostil. Also known as Cytotec [59122 6-2] C22H2gO, (a 1 1 mixture of (+/ —) methyl-ll-alpha,16-dihydroxy-16-methyl-9-oxoprost-13E-en-l-oate) (7), this agent is a light yellow liquid that is soluble in water. The methods for preparation are available (8). 

Ethers of benzenepentol have been obtained by Dakin oxidation of the appropriately substituted acetophenone. Thus, the oxidation of 2-hydroxy-3,4,6-ttimethoxyacetophenone and 2-hydroxy-3,4,5-ttimethoxyacetophenone with hydrogen peroxide ia the presence of alkali gives l,2-dihydroxy-3,4,6-ttimethoxybenzene and l,2-dihydroxy-3,4,5-ttimethoxybenzene, respectively further methylation of these ethers yields the pentamethyl ether of benzenepentol (mp 58—59 degC) (253). The one-step aromatization of myoinositol to produce esters of pentahydroxybenzene is achieved by treatment with carboxylic acid anhydrides ia DMSO and ia the presence of pyridine (254) (see Vitamins). 6-Alkyl- or... 

N-ethyl kanamycin A (153) has some resistance to APH(3 ), ANT(2 ), and AAC(3). Butakacin [59733-86-7] C22H N 0 2 t i l-A/-(3)-2-hydroxy-4-aminobutyl derivative of kanamycin A (154), has antimicrobial properties similar to amikacin. A similar effect was seen with the l-A/-(l,3-dihydroxy-2-propyl) derivative of kanamycin B, propikacin [66887-96-5] C22H42N 022 (155). Methylation of the 6 -amine reduces susceptibility to AAC(6 ) (156). 

Animals caimot synthesize the naphthoquinone ring of vitamin K, but necessary quantities are obtained by ingestion and from manufacture by intestinal flora. In plants and bacteria, the desired naphthoquinone ring is synthesized from 2-oxoglutaric acid (12) and shikimic acid (13) (71,72). Chorismic acid (14) reacts with a putative succinic semialdehyde TPP anion to form o-succinyl benzoic acid (73,74). In a second step, ortho-succmY benzoic acid is converted to the key intermediate, l,4-dihydroxy-2-naphthoic acid. Prenylation with phytyl pyrophosphate is followed by decarboxylation and methylation to complete the biosynthesis (75). 

The molecular features of covalent hydration are also present in the dihydroxy series, i.e., in pteridine-2,6-dione (30) and in pteridine-4,6-dione. The latter compound is hydrated only at the C(7)—N(8) double bond, whereas (30) forms two hydrated species, 7-hydroxy-7,8-dihydro- (29) and 4-hydroxy-3,4-dihydro-pteridin-2,6-dione (31) (equation 8). Structure (29) is thermodynamically the more stable substance (31) is formed more rapidly in solution but disappears slowly with time (63JCS5151). Insertion of a 4-methyl group greatly reduces the extent of 3,4- in favour of 7,8-hydration by a blocking effect . 

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