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31.
In petals of Silene dioica, gene P controls the 3′-hydroxylation of the anthocyanin B-ring and the hydroxylation pattern of the hydroxycinnamoyl acyl group bound to the 4″'-hydroxyl group of rhamnose of anthocyanidin 3-rhamnosyl(1→6)glucoside-5-glucoside. In this paper, experiments are presented which show that gene P is involved in the hydroxylation of p-coumaroyl-CoA to caffeoyl-CoA, which is then used both as a precursor in anthocyanin biosynthesis and as a substrate for the final acylation. 相似文献
32.
Five spirostanol glycosides and two furostanol glycosides were isolated from Dioscorea floribunda. In addition to the IR spectra of the free glycosides and the MS of the peracetates and permethyl ethers, the most effective method for structural determination proved to be the NMR spectra of the free saponins in pyridine-d5. 相似文献
33.
Two new saponins, agavasaponin E and agavasaponin H have been isolated from the methanolic extract of Agave americana leaves and their structures elucidated. Agavasaponin E is 3-O-[β-d-xylopyranosyl-(1→2glc1)-α-l-rhamnopyranosyl-(1→4)-α-l-rhamnopyranosyl-(1→3glc 1)-β-d-glucopyranosyl-(1→4)-β-d-glucopyranosyl-(1→4)-α-d-galactopyranosyl]-(25R)-5α-spirostan-12-on-3β-ol, whereas agavasaponin H is 3-O-[β-d-xylopyranosyl-(1→2 glc 1)-α-l-rhamnopyranosyl-(1→4)-α-l-rhamnopyranosyl-(1→3 glc 1)-β-d-glucopyranosyl-(1→4)-β-d-glucopyranosyl-(1→4)-β-d-galactopyranosyl]-26-O-[β-d-glucopyranosyl]-(25R)-5α-furostan-12-on-3β,22α,26-triol. 相似文献
34.
Two new saponins, yuccoside C and protoyuccoside C, have been isolated from the methanolic extract of Yucca filamentosa root and their structures elucidated. Yuccoside C is 3-O-[α-d-galactopyranosyl-(1 → 2)-β-d-glucopyranosyl-(1 → 4)-β-d-glucopyranosyl]-(25S)-5β-spirostan-3β-ol, whereas protoyuccoside C is 3-O-[α-d-galactopyranosyl-(1 → 2)-β-d-glucopyranosyl-(1 → 4)-β-d-glucopyranosyl]-26-O-[β-d-glucopyranosy]-(25S)-5β-furostan-3β,22α,26-triol. 相似文献
35.
Hassan-Fahmi Aly Hans Geiger Ursula Schücker Hugh Waldrum George Vander Velde Tom J. Mabry 《Phytochemistry》1975,14(7):1613-1615
Ten glycosides of kaempferol and quercetin, including the hitherto unknown kaempferol and quercetin 3-rutinoside-7-rhamnosides, have been isolated from Equisetum silvaticum L. 相似文献
36.
A water-soluble root extract of Angelica archangelica subsp. litoralis afforded, in addition to adenosine, coniferin and the two known dihydrofurocoumarin glycosides, apterin and 1′-O-β-d-glycopyranosyl-(S)-marmesin (marmesinin), two new dihydrofuranocoumarin glycosides, 1′-O-β-d-glucopyranosyl-(2S, 3R)-3-hydroxymarmesin, and 2′-β-d-glucopyranosyloxymarmesin. For the latter a 2S-configuration was demonstrated, the stereochemistry at position 1′ remaining undefined. Roots of A. silvestris similarly afforded 1′-O-β-d-glucopyranosyl-(2S, 3R)-3-hydroxymarmesin. By correlation with the aglycone 2S,3R)-3-hydroxymarmesin obtained in this work, the absolute configurations (2S,3R) were established for the known dihydrofurocoumarin diesters smirniorin and smirnioridin. 相似文献
37.
A Triosteum-feeding species of Sympistis is described from eastern North America: Sympistis forbesi
sp. n. Identity of the new species is most reliably determined from larval morphology and host plant association—both adult scaling and genitalic characters overlap with those of Sympisitis chionanthi, a Chionanthus and Fraxinus feeder. 相似文献
38.
The anthochlor complement of Coreopsis mutica has been determined. The compounds observed were all glycosidic derivatives of sulphuretin, being the mono- and di-glucosides and two new glucosidic derivatives acylated with caffeic acid. 相似文献
39.
Harald Greger 《Biochemical Systematics and Ecology》1978,6(1):11-17
Leaf flavonoids of 13 Anacyclus taxa have been identified and compared. The most common compounds are 3-, 7- or 5-glycosylated flavonols which, together with the accumulation of 2 diosmetin 7-glycosides, help to delimitate species groups according to recent morphological and cytological findings. In addition to quercetagetin, quercetagetin 3'-methyl ether, patuletin and spinacetin have been isolated as 7-glucosides from the yellow disc and ray flowers of Anacyclus radiatus. The distribution patterns of polyacetylenes and particularly related amides, characterize different Anacyclus species and apparently contribute to a more natural interpretation of relationships with other genera, which may also be underlined by the distribution of cyanogenic glycosides. 相似文献
40.
In this review, structures of natural products isolated from the soft corals of genus Cladiella and their biological activities are described. 相似文献