Pancratium

Pancratium littorale Jacq., native to Hawaii, which exhibits anti-cancer activity. 

Pancratistatin (15) (Figure 7.4) was isolated by Pettit and co-workers from the roots of Pancratium littorale, which exhibits anticancer activity against murine P-5076 ovarian sarcoma and P-388 lymphocytic leukemia [10]. Rigby and coworkers performed photocycHzation as a key step in the total synthesis of 15,... 

Unique total synthesis of antitumor alkaloid, pancratistatin (97), which was isolated from the roots of the Hawaiian Pancratium littorale Jacq., by / -azido-nation reaction of triisopropylsilylenol ether (183) with Phl=0-TMSN3 as the key reaction has been accomplished by Magnus and Sebhat [138] (Scheme 47). 

The discovery of lycorine-1-O-p-D-glucoside (4) and the related alkaloid pseudolycorine-1 -0- (i-D-glucoside (10) in Pancratium biflorum represented the first report of the natural occurrence of glucosyloxy alkaloids in the family Amaryllidaceae (73). The structures of 4 and 10 were deduced from H NMR and mass spectroscopy coupled with the observation that hydrolysis of the glycosides with emulsin afforded lycorine (1) and pseudolycorine (9), respectively, together with D-glucose. 

Trianthine (21), which is the optical antipode of zephyranthine, has been isolated from Pancratium trianthum (75). Caribine (22), which was found in... 

O. elwesii Hook., Haemanthus puniceus L., Leucojum aestivum L. var. pulcheUum Salisb., L. vernum L., Pancratium maritimum L., Sprekelia formosissima Herb., Stembergia lutea (L.) Ker-Gawl., and Vallotta speciosa L Herb. 

The availability of the enantiomeric alkaloids vittatine (284) and crinine in labeled form through separate feeding experiments with labeled 343 in Pancratium maritimum L. and Nerine bowdenii, respectively, provided experiments which indicated the absolute configuration of narciclasine. Thus, the two alkaloids were obtained from [3, 5 -3H2]-O-methylnorbelladine. Experiments with multiply labeled 343 have previously shown that no 3H loss takes place during the biosynthesis,... 

Hymenocallis littoralis (spider lily) [bulb], H. spp., Pancratium littorale, P. spp. (Amaryllidaceae)... 

Leucojum aestiuum, Lycoris radiata, Narcissus tazetta, Pancratium biflorum, ephyranthes carinatus (Amaryllidaceae)... 

Dimethoxy-4 -hydroxyacetophenone Pancratium biforum (Amaryllidaceae) [bulb] COX (PGS), 5-LOX... 

Noteworthy results in the phytochemical studies, the N-oxides of several Amaryllidaceae alkaloids have been found for the first time in Amaryllidaceae plants, accompanied by the corresponding free bases (52) ungiminor-ine A-oxide (10) (from Pancratium maritimum), and O-methyllycorenine A-oxide (329) and homolycorine A-oxide (330) (from Lapiedra maritinezii). The stereochemistry of their nitrogen atoms was deduced based on 2D NOESY experiments. Furthermore, it has been established that these A-oxide derivatives are genuine natural products, and not artifacts, by the demonstration that the free bases are not converted into A-oxides when subjected to the same extraction procedure. It is noteworthy that the A-oxides have been isolated accompanied by the corresponding free bases. 

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... 

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