Hippeastrum hybrids

A number of mannose-specific agglutinines (lectins) from Galanthus nivalis, Hippeastrum hybrid, Narcissus pseudonarcissus, Listera ovata, Cymbidium hybrid, Epipactis helleborine, and the N-acetylglucosamine-specific lectin from Urtica dioica have been found to inhibit HIV-1 and HIV-2 infection at similar concentrations as dextran sulfate (IC50 0.2 to 0.6 fig/ml), or even lower (IC50 0.04 to 0.08 pg/ml. Akin to sulfated polysaccharides, the plant lectins also exhibit activity against various enveloped viruses other than HIV, i.e., HSV-1, HSV-2, CMV, RSV, and influenza virus. Plant lectins would primarily interfere with the virus-cell fusion process. Their precise mode of action remains to be resolved. 

Tazettine (298) has been isolated from Crinum americanum (leaves) (76), C. giganteum (27), Hippeastrum equestre (bulbs) (40), Hippeastrum hybrids (bulbs) (42), Hymenocallis expansa (bulbs and leaves) (48), Lycoris radiata (bulbs) (60), Narcissus tazetta (90), N. cantaricus (whole plants) (65), Pancratium maritinum (bulbs) (96), and Stembergia sicula (whole plants) (103). Pretazettine (300) has been found in N. pallidiflorus (whole plants) (76), N. panizzianus (whole plants) (79) (aerial and bulbs) (80), S. culsiani (bulbs) (102), and Zephyranthes flava (fresh mature seeds) (70S). Tazettine (298), pretazettine (300), littoraline (301), and marconine (302) have been isolated... 

The alkaloid, C16H17NO4 (mp 219° [a]]j +74° in CHCI3), was isolated from the Hippeastrum hybrid Anna Powlowna . It forms pi crate (mp 249° decomp.) and hydriodide (mp 221° decomp.) salts. The compound gives a red color with concentrated sulfuric acid. It is classified as a crinine-type alkaloid because the IR-spectrum of annapawine is very similar to that of powellamine and crinine (32). 

Dihydrohaemanthidine (hippawine) has been isolated from the Hippeastrum hybrid Queen of the Whites (32), and dihydrohaeman-thamine was detected in Crinum powellii var. harlemense (20). 

Lectins Mannose specific lectins Cymbidium hybrid, Epipactis hetleborine, Hippeastrum hybrid. Listeria ovala, Machaerium biovulal-urn, M. lunatus, Gerardia savaglia HIV CMV Cell fusion of HIV replication. Syncytium formation. [12] [46]... 

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