dihydroxy compound
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2010 ◽  
Vol 174 ◽  
pp. 401-404
Author(s):  
Rui Xin Xu ◽  
Guang Xue Chen

The anion UV-curing water soluble prepolymer was synthesized with toluene diisocyanate, dihydroxy compound, dihydroxyalkyl carboxylic acid and polyurethane acrylate. The structure of the prepolymer was characterized by infrared spectroscopy. The effect of different photoinitiators, pigment content, drying technology on the curing speed of ink was also researched. The results shown that the photoinitiator system 819DW and MBF was best matched with the yellow pigment, cyan pigment and black pigment, the optimum content of the pigment was about 10 percent, 10 percent and 11 percent. The photoinitiator system 819DW and 500 was best matched with the magenta pigment, the optimum content of the pigment was about 10 percent.Under the conditions of this experiment, the best pigment content of the yellow, magenta, cyan, black was about 6 percent, 7 percent, 6 percent and 7 percent. The curing rate without pre-drying increased.


1994 ◽  
Vol 47 (8) ◽  
pp. 1509 ◽  
Author(s):  
RM Carman ◽  
AC Garner ◽  
KD Klika

2,9-Dihydroxy-1,8-cineole (7a) and the corresponding 2,10-dihydroxy compound (8a) are present in the urine of brushtail possums fed a diet enhanced with 1,8-cineole (1). Chemical syntheses of these two novel metabolites are described.


1979 ◽  
Vol 32 (5) ◽  
pp. 1107 ◽  
Author(s):  
DJ Collins ◽  
WA Matthews ◽  
GM Stone

Hydroboration of an inseparable mixture of 2,8-dimethoxy-5,6-dihydrochrysene (5a) and 2,8-dimethoxy-4b-methyl-4b,5,6,12-tetrahydrochrysene (6a) followed by oxidation with alkaline hydrogen peroxide gave a mixture of (4bα,10bβ,11β)-2,8-dimethoxy-4b-methyl-4b,5,6,10a,11,12-hexahydrochrysen-11-ol (10a) and its (4bβ,10bβ,11β) isomer(11a). Reduction of the methanesulfonate ester of (10a) with lithium aluminium hydride in ether gave 2,8-dimethoxy-4b-methyl-trans-4b,5,6,10b,11,12- hexahydrochrysene (2b), identical with material prepared by another route. Reduction of the methanesulfonate of (4bβ,10bβ,l1β)-2,8-dimethoxy-4b-methyl-4b,5,6,10a,11,12-hexahydrochrysen- 11-ol afforded 2,8-dimethoxy-4b-methyl-cis-4b,5,6,10b,11,12-hexahydrochrysene (12), demethylation of which afforded 4b-methyl-cis-4b,5,6,10b,11,12-hexahydrochrysene-2,8-diol (14b). Dehydration of the mixture of the 11-epimeric alcohols (10a) and (lla) with phosphorus oxytrichloride in pyridine yielded pure 2,8-dimethoxy-4b-methyl-4b,5,6,12-tetrahydrochrysene (6a) which was demethylated with methylmagnesium iodide to give the corresponding dihydroxy compound (9). Other compounds prepared in the course of examining possible routes to (9) and (14b) include 13,13-dichloro-2,8-dimethoxy-4b,5,6,10b,11,12-hexahydro-4b,10b-methanoch rysene (3a), 1-bromo- 2,8-dimethoxy-5,6-dihydrochrysene (5b), and 11-bromo-2,8-dimethoxy-4b-methy1-4b,5,6,12-tetra- hydrochrysene (7). The oestrogenic activities of some of the new angularly methylated hydrochrysenes and of 9α- methyloestradiol (15) are reported.


1974 ◽  
Vol 29 (7-8) ◽  
pp. 374-383 ◽  
Author(s):  
Jochen Berlin ◽  
Peter Kiss ◽  
Dieter Müller-Enoch ◽  
Dieter Gierse ◽  
Wolfgang Barz ◽  
...  

Abstract Cell suspension culture of Phaseolus aureus, Glycine max and Pisum sativum have been used to determine the extent of chalcone and isoflavone catabolism. The A-rings of calcones and isoflavones with both resorcinol and phloroglucinol pattern of sub­stitution have unequivocally been shown to be degraded as measured by carbon dioxide production The earlier described catabolic pathway of chalcones with the B-ring liberated as a substituted benzoic acid has been verified using another chalcone. With the use of various 14C-labelled isoflavones it could be demonstrated that essentially all carbon atoms are introduced into catabolic reactions. Incorporation of 4',7-dihydroxyisoflavone (daidzein) into insoluble polymeric material has been shown to proceed via the 3',4',7-trihydroxyisoflavone. 3'-Hydroxylation and subsequent polymeri­sation of the orto-dihydroxy compound can completely be inhibited by using anaerobic conditions which favour glucoside formation instead. 4'-O-Methylgroups in isoflavones prevent the phenolase catalzyed 3'-hydroxylation and thus the incorporation of isoflavones into polymeric structures. 6,7-Dihydroxy substituted insoflavones when fed to cell cultures are not polymerized by phenolase but are rather converted to glycosides.


1972 ◽  
Vol 130 (1) ◽  
pp. 27-35 ◽  
Author(s):  
P. Sims

The synthesis of dibenz[a,c]anthracene 10,11-oxide is described. The oxide was unstable and was rapidly decomposed with cold mineral acid into a mixture of 10- and 11- hydroxydibenz[a,c]anthracene. The oxide was converted by rat liver microsomal preparations and homogenates into a product that is probably 10,11-dihydro-10,11-dihydroxydibenz[a,c]anthracene and which was identical with the metabolite formed when dibenz[a,c]anthracene was metabolized by rat liver homogenates. The oxide did not react either chemically or enzymically with GSH. 10,11-Dihydrodibenz[a,c]anthracene and 10,11-dihydrodibenz[a,c]anthracene 12,13-oxide were both metabolized by rat liver preparations into trans-10,11,12,13-tetrahydro-10,11-dihydroxydibenz[a,c] anthracene and the oxide was converted chemically into this dihydroxy compound, and it reacted chemically but not enzymically with GSH. In the alkylation of 4-(p-nitrobenzyl)pyridine, the ‘K-region’ epoxide, dibenz[a,h]anthracene 5,6-oxide, was more active than either dibenz[a,c]anthracene 10,11-oxide or 10,11-dihydrobenz[a,c]anthracene 12,13-oxide.


1967 ◽  
Vol 06 (01) ◽  
pp. 32-43 ◽  
Author(s):  
K. Liewendahl ◽  
V. Kivikangas ◽  
B.-A. Lamberg

Summary 126I-labelled iodochloroxyquinoline (125ICOQ, Vioform®, CIBA) was given orally in tracer doses to 3 euthyroid and 3 hyperthyroid subjects. Samples of plasma, urine and faeces were closely analysed.The formation of 3 metabolites was demonstrated: a) a glucosiduronate (125ICOQ-gluc), b) a sulphate ester (125ICOQ-sulph) and c) an unidentified compound (125ICOQ-X) which may possibly be a dihydroxy compound.The main compound in urine was 125ICOQ-gluc. The proportion of this compound increased with time, while that of 125ICOQ and 125ICOQ-X decreased. The percentage 125ICOQ-sulph remained unchanged. The conjugates were also found in plasma but the radioactivity was mainly distributed between 125ICOQ and 125ICOQ-X. The protein-bound radioactivity in the plasma was located to albumin. More than 90 per cent of the plasma radioactivity could be removed with 3 butanol extractions. A small decrease in butanol extractability with time was noted.Comparison of the ratio between water-soluble and butanol soluble compounds in the plasma dialysate and in the corresponding urine revealed a similar ratio, indicating a similar renal clearance for all the substances. The decrease of 125ICOQ and 125ICOQ-X in the urine with time may partly be due to a firmer binding of these compounds to the plasma proteins. The spontaneous increase in the excretion of radioactivity in the urine (9) is probably due to an adaptation of the liver enzymes for forming conjugates.Faeces contained only minute amounts of the conjugates which, however, indicated the existence of an enterohepatic circulation for 125ICOQ. The main faecal metabolites were original 125ICOQ and 125ICOQ-X. The site of formation of 125ICOQ-X is assumed to be the liver or gastrointestinal tract.In none of the chromatograms of plasma, urine or faeces could any radioactive iodide or thyroidal hormones be demonstrated.


1967 ◽  
Vol 20 (12) ◽  
pp. 2691 ◽  
Author(s):  
KA Harper

The molecular changes undergone by 3,7,4?-trihydroxyflavylium perchlorate in aqueous methanolic solutions with increasing pH were followed by polarography and spectrometry, and the effect of the hydroxyl at C3 observed by comparison with the behaviour of 7,4?- dihydroxyflavylium perchlorate. The trihydroxyflavylium ion is less stable above pH 2 than the dihydroxy compound and forms the open-chain α-diketone, probably via the 3-keto pseudobase. The stability of the enolic form of the pseudobase increases at higher pH and is favoured from pH 5 to pH 9. At pH 6.5 the anhydrobase appears in the equilibrium mixture and at pH 9 becomes stabilized by ionization. Although the α- hydroxychalcone was not detectable at lower pH, at pH 10 ring opening gives the ionized a-hydroxychalcone, rather than the ionized diketone, and equilibrium shifts in this direction as the pH is raised further.


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