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PHARM. DChemical Pharmacognosy- I
Lecture 28May 11th, 2011
LACTONE GLYCOSIDES
M. M. AhsanAhsan KhalidKhalid, , B.PharmB.Pharm, Pharm. D, Pharm. DM.PhilM.Phil Scholar (RIPS/RIU)Scholar (RIPS/RIU)
HIPSHIPS--HUKICHUKIC
Lactone glycosides• Coumarin• Classified as a simple phenylpropanoid• occurs in Tonka Beans, sweet vanila grass
( Anthoxanthum odoratum; Fam Poaceae), sweet clover (Melilotus albus/officinalis;Fabaceae) etc.
• Formerly used as flavoring agent, FDA banned the use of coumarin and coumarin containing materials as flavoring agent (con’t)
Lactone glycosides
– Bishydroxycoumarin (Dicumarol) is obtained from improperly cured leaves and flowering tops of Melilotus officinalis(Fabaceae)
– Anti - Coagulant property (determine by APTT) as prophylaxis and treatment of venous thrombosis and pulmonary embolism
– Interfere with Vit K action
Lactone glycosides• Aside from coumarin (lactone of o-hydroxy
cinnamic acid), other hydroxylated coumarin derivatives occurring in plants are:
1. Skimmin - Japanese star anise 2. Aesculin - horse chestnut tree3. Daphnin - Mezereum4. Scopolin - Belladonna5. Limettin - Citrus trees
Santonica USP VIII (1905)Synonym: Levant, Aleppo, Alexandria
Wormseed, Semen Cinae, sea wormseed
Origin: dried unexpanded flower heads of Artemisia cina (Asteraceae)
Constituent: chief: β - santonin(sesquiterpene lactone),
artemisin(crystalline lactone)Use: Anthelmintic (roundworm e.g. ascaris)
little effect on threadworm, no effect on Taenia
Santonica- action is due to spasmodic contraction of the GIT
rendering worm incapable of movement -- excreted in bowel; should not be followed by a purgative
Allied drug in the PhillipinesSeeds of Quisqualis indica (Combretaceae)known as niog - nioganused as anthelmintic agent
Cantharides NF X (1955)
Synonym: Spanish flies, Russian flies, Blistering Flies
Origin: dried insects of Cantharis vesicatoria(Meloidae)
Constituent: Cantharidin (lactone or anhydride of cantharidic acid)
Use: Irritant, Vesicant, Rubefacient removes warts (topically)
Internally: excreted by kidney, irritating to urinary tract --- resulting in priapism
CantharidesNote:
Popular as Aphrodisiac - Dangerous and reported can cause death
Insect found in shrubs of Caprifoliaceae and Oleaceae
Mature insect - brilliant green with metallic luster
Psoralens• Photosensitizing furocoumarin• Common cause of phototoxicity
1. Methoxsalen (8-methoxypsoralen, Xanthotoxin)- Present in the cremocarp of Ammi majus(Apiaceae)- Used to facilitate repigmentation in idiopathic vitiligo (Leukoderma)- Symptomatic control of severe,
disabling psoriasisCAUTION: Therapy is carcinogenic, cataract
development, Actinic degeneration of skin(Photochemical degeneration)
Psoralens2. Trioxsalen (4,5’,8 - trimethoxypsoralen)
- synthetic furocoumarin- treatment of vitiligo
3. Khellin (Visnaga, khella)- furochrome found in fruits of Ammi visnaga (toothpickweed; Apiaceae)- Vasodilator (bronchial asthma andangina pectoris, - Visnadin mild inotropic – dilate coronary
vessels- used as urethral spasm and renal colic
Psoralens
• Interactions– Hepatotoxic herbs - additive– St. John wort -photosensitivity– Lifestyle – alcohol leads to hepatotoxicity