《药物化学》课程PPT教学课件（Medicinal chemistry）第十二章 维生素 Vitamin

Chapter 12 Vitamins Section 1 fat soluble vitamins Section 2 Water soluble vitamins

Chapter 12 Vitamins • Section 1 Fat Soluble Vitamins • Section 2 Water Soluble Vitamins

Vitamin Vitamin is any of various fat-soluble or water soluble organic substances essential in minute amounts for normal growth and activity of the body and obtained naturally from plant and animal foods Vitamins act as catalysts; very often either the vitamins themselves are coenzymes or they form integral parts of coenzymes

Vitamin • Vitamin is Any of various fat-soluble or water￾soluble organic substances essential in minute amounts for normal growth and activity of the body and obtained naturally from plant and animal foods. • Vitamins act as catalysts; very often either the vitamins themselves are coenzymes, or they form integral parts of coenzymes

Classification Vitamins are divided into two groups: fat soluble vitamins and water-soluble vitamins The fat-soluble vitamins include vitamin a.d. e and K The water-soluble vitamins include the vitamin B complex and vitamin c, etc

Classification • Vitamins are divided into two groups: fat￾soluble vitamins and water-soluble vitamins. • The fat-soluble vitamins include vitamin A, D, E, and K. • The water-soluble vitamins include the vitamin B complex and vitamin C, etc

Section 1 Fat Soluble vitamins Fat-soluble vitamins are stored in the liver and fatty tissues, and are eliminated much more Slowly than water-Soluble vitamins Diseases caused by a lack of fat-soluble vitamins are rare, but some health problems may decrease the absorption of fat, and in turn decrease the absorption of vitamins a, d, E and K and result in deficiency

Section 1 Fat Soluble Vitamins • Fat-soluble vitamins are stored in the liver and fatty tissues, and are eliminated much more slowly than water-soluble vitamins. • Diseases caused by a lack of fat-soluble vitamins are rare, but some health problems may decrease the absorption of fat, and in turn, decrease the absorption of vitamins A, D, E and K and result in deficiency

Definition of vitamin a Vitamin a is the collective name for a group of fat-soluble vitamins . the most useful form of the vitamin is retinol often called vitamina as it is the active form in the body Retinol (an alcohol can only be found in animal sources and can be converted by the body into retinal an aldehyde and retinoic acid a carboxylic acid), other active forms of vitamin a

Definition of Vitamin A • Vitamin A is the collective name for a group of fat-soluble vitamins. The most useful form of the vitamin is retinol, often called vitamin A1 as it is the active form in the body. • Retinol (an alcohol) can only be found in animal sources and can be converted by the body into retinal (an aldehyde) and retinoic acid (a carboxylic acid), other active forms of vitamin A

Structure of Vitamin A1 H3C CH3 CH- CH3 OH Vitamin A, has four double bounds (all trans )at positions 2, 4, 6, 8 on unsaturated side chain containing 9 carbon atoms There are three methyl groups at positions 2 6,6 of Cyclohexenyl ring attached to position 9 on the side chain

Structure of Vitamin A1 • Vitamin A1 has four double bounds (all trans ) at positions 2,4,6,8 on unsaturated side chain containing 9 carbon atoms. • There are three methyl groups at positions 2´ , 6´ , 6´ of Cyclohexenyl ring attached to position 9 on the side chain. H3C CH3 CH3 OH CH3 CH3

Vitamin a deficiency(VAD) VaD is the leading cause of preventable blindness in children and raises the risk of disease and death from severe infections. In pregnant women VAD may increase the risk of maternal mortality VAD is a public health problem in 118 countries especially in Africa and South-east asia Vitamin a is used for treatment of vad

Vitamin A deficiency (VAD) • VAD is the leading cause of preventable blindness in children and raises the risk of disease and death from severe infections. In pregnant women VAD may increase the risk of maternal mortality. • VAD is a public health problem in 118 countries, especially in Africa and South-east Asia. • Vitamin A is used for treatment of VAD

History In 1913, vitamin a was found in fish liver oil or yolk In 1931, retinol was isolated in mammal and salt water fish, which was called vitamin A Afterward 3-dehydroretinol was isolated in fresh water fish, which was called vitamin A2 、CH3 CH3 CH3 H3C CH OH CH3 CH3 Vitamin a2 Vitamin al

History • In 1913, vitamin A was found in fish liver oil or yolk. • In 1931, retinol was isolated in mammal and salt water fish, which was called vitamin A1 . • Afterward, 3-dehydroretinol was isolated in fresh water fish, which was called vitamin A2 . H3C CH3 CH3 OH CH3 CH3 Vitamin A1 H3C CH3 CH3 OH CH3 CH3 Vitamin A2

Beta carotene is called provitamin a, which can be converted to retinol by the body n the liver, one molecule of beta carotene can be cleaved by an intestinal enzyme into two molecules of retinol so beta carotene can also be good sources of retinol

• Beta carotene is called provitamin A, which can be converted to retinol by the body. • In the liver, one molecule of beta carotene can be cleaved by an intestinal enzyme into two molecules of retinol, so beta carotene can also be good sources of retinol

Stability Vitamin a is sensitive to ultraviolet or oxidation by the air so the compound should be stored in an aluminium container or vitamin e oil Vitamin a is not stable to acid and dehydration of vitamin a results in a dehydrate of vitamin a that is only 0.4%potency of vitamin A

Stability • Vitamin A is sensitive to ultraviolet or oxidation by the air. So the compound should be stored in an aluminium container or vitamin E oil. • Vitamin A is not stable to acid and dehydration of vitamin A results in a dehydrate of vitamin A that is only 0.4% potency of vitamin A