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1.
Ultrasensitive bioluminescence immunoassays for the determination of peptides and proteins (illustrated with human urinary kallikrein, bradykinin and the determination of human urinary kallikrein antibody titres) have been developed. The usable ranges of the standard curves are from 5 pg to 5000 pg per litre. The relative intra-assay coefficients of variation of the tests were between 2% and 6%, and the inter-assay coefficients of variation between 4% and 12%. 相似文献
2.
From three Mikania species, three new labdanic acid and two kaurenic acid derivatives have been isolated together with known compounds and four new germacranolides, differing only in the ester moiety. 相似文献
3.
The aerial parts of the South African composite Printzia laxa contain two manoyl oxides and three clerodane derivatives together with two further acids, which belong to a new type of diterpene, biogenetically closely related to the clerodanes. The structures have been elucidated by spectroscopic methods. The constituents may indicate some relationship of Printzia to the tribe Astereae. 相似文献
4.
5.
The reinvestigation of the aerial parts of Wedelia trilobata afforded, in addition to known compounds, six new eudesmanolides, two ent-kaurenic acid derivatives as well as a degraded one. A corresponding hydroxy compound was present in Gnaphalium undulatum. From Aspilia parvifolia new ent-kaurenic acid epoxides were isolated. The structures were elucidated by spectroscopic methods. The chemotaxonomic situation is discussed briefly. 相似文献
6.
Investigation of the North American species Psilostrophe villosa afforded, in addition to known compounds, five new sesquiterpene lactones, which all turn out to be modified pseudoguaianolides, most of them closely related to hymenolide. However, one of the lactones is a new type of nor-pseudoguaianolide. Furthermore a new monoacetylated borneol-β-D-glucoside is present. The chemotaxonomic situation is discussed briefly. 相似文献
7.
8.
Four thiocyanatopyrazole derivatives were synthesized and their fungistatic activity was demonstrated in vitro against a number of dermatophytic fungi. In Trichophyton mentagrophytes, the most active compound induced an unusual increase of the plasma membrane with production of intra and extracytoplasmic complexes, a deterioration of nuclear and mitochondrial membranes and a formation of autophagic-like vacuoles. Plasmolysis, accompanied by an almost complete disorganization of cytoplasmic structures, seemed to be the final event. A possible mechanism of action of the compounds was discussed.Investigation supported by a grant from Consiglio Nazionale delle Ricerche of Italy (Contract No. 7500536). 相似文献
9.
Summary. New γ-amino esters and amides were prepared by a radical 1,4-addition of carbon radicals to acrylic derivatives. α-Amino acids
derivatives holding chiral auxiliaries as radical precursors and different chiral olefins were used and chiral induction on
the C-γ center was discussed. 相似文献
10.