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71.
Kazu Kurosawa W.David Ollis Ian O. Sutherland Otto R. Gottlieb Alaide B. de Oliveira 《Phytochemistry》1978,17(8):1405-1411
Additionally to the cinnamylphenols described in a previous paper, wood samples of Machaerium mucronulatum and M. villosum contain isoflavones, besides (?)-duartin, (?)- and (±)-mucronulatol [(3S)- and rac-7,3′-dihydroxy-2′,4′-dimethoxyisoflavan], (?)-mucroquinone [(3S)-2-methoxy-5-(7-hydroxy-8-methoxychroman-3-yl)-1,4-benzoquinone] and (+)-mucronucarpan [(6aS,11aS)-2,10-dihydroxy-3,9-dimethoxypterocarpan]. The constitutions of mucronulatol, mucroquinone and mucronucarpan were deduced by spectra and degradations, and confirmed by syntheses. 相似文献
72.
Bark and wood of the creeper Dalbergia variabilis contain the previously described friedelin, O-acetyl-oleanolic acid, formononetin, 8-O-methylretusin, (+)-vestitol, (±)-mucronulatol, (+)- and (±)-medicarpin, besides (+)-variabilin [(6aR,11aR)-6a-hydroxy-3,9-dimethoxypterocarpan]. This structure was confirmed by the conversion of (+)-variabilin into di-O-methylcoumestrol. 相似文献
73.
Kazu Kurosawa W.David Ollis Brian T. Redman Ian O. Sutherland Herbert M. Alves Otto R. Gottlieb 《Phytochemistry》1978,17(8):1423-1426
The absolute configurations of isoflavans and isoflavanquinones isolated from Cyclolobium, Dalbergia and Machaerium species were established by comparison of their ORD curves with that of (3S)-5,7,3′,4′-tetra-methoxyisoflavan and (3S)-7,4′-dimethoxyisoflavan-2′,5′-quinone, respectively. The assignments were checked by the ozonolysis of the isoflavan (?)-duartin to (R)-paraconic acid and the oxidation of isoflavans to isoflavanquinones. The PMR spectra of the dihydropyran ring of the isoflavans are discussed in terms of the preferred conformation of this ring. 相似文献
74.
75.
In a case of quinine-induced agranulocytosis marrow culture studies confirmed the inhibitory effect on the patient''s cells of equivalent therapeutic plasma concentrations of quinine. Similar concentrations had no effect on normal marrow cells. Quinidine, the stereoisomer of quinine, had no effect on either cells from the patient or normal cells. The results encourage the use of in-vitro bone marrow cultures for identifying drugs responsible for agranulocytosis. 相似文献
76.
77.
Xanthan with various pyruvic acid and acetate contents has been prepared from a single commercial polysaccharide sample using optimised chemical conditions (acid and alkali hydrolysis, respectively) for removal of acetal and acyl groups. The only significant change found on analysis of the modified xanthans was loss of pyruvic acid and/or acetate; no low moleculur weight carbohydrate-containing material was released. Contrary to some previous reports, evidence is presented to show that the pyruvic acid acetal and o-acetyl contents of xanthan do not affect solution viscosity. The viscosities of native, pyruvate-free and pyruvate/acetate-free xanthan solutions (0·3% w/v) were similar at shear rates 8·8–88·3 s?1 in both distilled water and 1% KCl. Over the concentration range 0·2-1·5%, the viscosities of native and pyruvate-free xanthan at 10 s?1 were similar. The viscosity increase on addition of 1% KCl to salt-free xanthan solutions was independent of pyruvic acid acetal substitution. Our results suggest that xanthan samples with various pyruvic acid acetal and o-acetal contents, prepared under different fermentation conditions of Xanthomonas campestri should not normally be used for assessing the contribution of these groups to solution viscosity. 相似文献
78.
R P Taylor C J Reist W M Sutherland A Otto R H Labuguen E L Wright 《Journal of immunology (Baltimore, Md. : 1950)》1992,148(8):2462-2468
We have used the avidin/biotin system to construct soluble, cross-linked bispecific heteropolymers containing mAb to both the primate E C receptor and the DNP group. These heteropolymers facilitate in vitro binding of DNP-bovine gamma-globulin (DNP-BGG) to both human and squirrel monkey E. Intravenous injection in squirrel monkeys of DNP-BGG followed by heteropolymer leads to E binding and clearance from the circulation of a significant fraction of both heteropolymer and DNP-BGG, without lysis or clearance of the E. This methodology may potentially be used to treat a variety of infectious diseases and other syndromes associated with blood-borne pathogens. 相似文献
79.
80.
J B Sutherland A L Selby J P Freeman F E Evans C E Cerniglia 《Applied microbiology》1991,57(11):3310-3316
The white rot fungus Phanerochaete chrysosporium metabolized phenanthrene when it was grown for 7 days at 37 degrees C in a medium containing malt extract, D-glucose, D-maltose, yeast extract, and Tween 80. After cultures were grown with [9-14C]phenanthrene, radioactive metabolites were extracted from the medium with ethyl acetate, separated by high-performance liquid chromatography, and detected by liquid scintillation counting. Metabolites from cultures grown with unlabeled phenanthrene were identified as phenanthrene trans-9,10-dihydrodiol, phenanthrene trans-3,4-dihydrodiol, 9-phenanthrol, 3-phenanthrol, 4-phenanthrol, and the novel conjugate 9-phenanthryl beta-D-glucopyranoside. Identification of the compounds was based on their UV absorption, mass, and nuclear magnetic resonance spectra. Since lignin peroxidase was not detected in the culture medium, these results suggest the involvement of monooxygenase and epoxide hydrolase activity in the initial oxidation and hydration of phenanthrene by P. chrysosporium. 相似文献