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