STEROIDS

• steroids possess a common structure – PERHYDROCYCLOPENTANOPHENANTHRENE NUCLEUS (RPS)

• includes cholesterol, bile acids, androgens, adrenocortical, adrenomedullary, estrogenic, and progestational hormones

CLASSIFICATION

STEROL

• Sterol• also known as steroid alcohols• occur naturally in plants, animals, and fungi, with the most

familiar type of animal sterol being cholesterol• TYPES:• Phytosterols – plant sterol ( campesterol, sitosterol,

and stigmasterol)• blocks cholesterol absorption sites in the human intestine, thus

helping to reduce cholesterol in humans• Zoosterol – animal sterol (cholesterol)• Ergosterol – sterol present in the cell membrane of fungi

BILE ACIDS

• Bile acids• are steroid acids found predominantly in the bile of

mammals and other vertebrates• are conjugated with taurine or glycine in the liver,

forming bile salts• Primary bile acids are those synthesized by the liver• Secondary bile acids result from bacterial actions in the colon

• 2 functions:• to remove unwanted cholesterol from the body • to aid in lipid digestion in the intestine

CARDIAC GLYCOSIDE

• Cardiac Glycosides• are glycosides of mostly C23-steroidal compounds• are called cardiac glycosides because they modify heart action

• MEDICINAL IMPORTANCE:• They are cardiotonics used to treat Congestive heart failure

(CHF)• They increase force of contraction of cardiac muscles without

increase oxygen consumption• Increase cardiac output• The diastolic phase last longer so decrease heart rate• Have diuretic effect due to increase amount of blood passing

through the kidney

STEROID HORMONES

• Steroid hormones• a steroid that acts as a hormone• can be grouped into five groups by the receptors to which

they bind: glucocorticoids, mineralocorticoids, androgens, estrogens, and progestogens

• Steroid hormones help control: • metabolism, inflammation, immune functions, salt and

water balance, development of sexual characteristics, and the ability to withstand illness and injury

CLASSES of STEROID HORMONES

• Glucocorticoids• Glucocorticoids originate in the adrenal cortex and affect

mainly metabolism in diverse ways; decrease inflammation and increase resistance to stress.

• Cortisol: dominant glucocorticoid in humans, synthesized from progesterone in the zona fasciculata of the adrenal cortex, involved in stress adaptation, elevates blood pressure and Na+ uptake, numerous effects on the immune system

• Mineralocorticoids• Mineralocorticoids originate in adrenal cortex and maintain salt

and water balance.• Aldosterone: the principal mineralocorticoid, produced from

progesterone in the zona glomerulosa of adrenal cortex, raises blood pressure and fluid volume, increases Na+uptake

CLASSES of STEROID HORMONES

• Estrogens• Estrogens originate in the adrenal cortex and gonads and primarily

affect maturation and function of secondary sex organs (female sexual determination)

• The natural estrogenic hormones are estradiol, estrone, and estriol, produced in the gonads, adrenals, and placenta

• Estradiol: an estrogen, principal female sex hormone, produced in the ovary, responsible for secondary female sex characteristics

• Androgens• Androgens originate in the adrenal cortex and gonads and primarily

affect maturation and function of secondary sex organs (male sexual determination)

• Testosterone: an androgen, male sex hormone synthesized in the testes, responsible for secondary male sex characteristics, produced from progesterone; most potent androgen in blood

CLASSES of STEROID HORMONES

• Progestins• Progestins originate from both ovaries and placenta, and

mediate menstrual cycle and maintain pregnancy• Progesterone: a progestagen, produced directly from

pregnenolone and secreted from the corpus luteum, responsible for changes associated with luteal phase of the menstrual cycle, differentiation factor for mammary glands

IDENTITY TESTS for STEROLS

IDENTIFICATION TEST

REAGENTS USED

POSITIVE RESULT

COMPOUNDS POSITIVE FOR

THE TEST

Rosenheim Reaction

CHCl3 + aq. Trichloroacetic acid sol’n

RED color BLUE color

sterol

Tortelli-Jaffe Reaction

Glacial Hac + sol’n of Br2 in CHCl3

GREEN color at the interface

sterol

IDENTITY TESTS for CHOLESTEROL

IDENTIFICATION TEST

REAGENTS USED

POSITIVE RESULT

COMPOUNDS POSITIVE FOR THE

TEST

Liebermann-Burchard’s test

Acetic anhydride + H2SO4

GREEN color Cholesterol

Salkowski reaction

+ CHCl3 soln+ H2SO4

RED color GREEN FLUORESCENCE

Cholesterol

IDENTITY TESTS for CHOLESTEROL

IDENTIFICATION TEST

REAGENTS USED

POSITIVE RESULT

COMPOUNDS POSITIVE FOR

THE TESTTschugaeff Method

Cholesterol in CHCl3 in glacial Hac + ZnCl2 and acetyl chloride + heat

RED color cholesterol

IDENTITY TEST for BILE ACIDS

IDENTIFICATION TEST

REAGENTS USED

POSITIVE RESULT

COMPOUNDS POSITIVE FOR

THE TESTMylius Reaction BLUE color in

transmitted light and needles, which appear YELLOW in reflected light

Cholic acid

Hammarsten Test HCl + alcohol+ heat

VIOLET color YELLOW

color

Cholic acid

Pettenkofer Reaction

+ heat RED color BLUISH RED

in several days

Cholic acid

IDENTITY TESTS for CARDIAC GLYCOSIDES

IDENTIFICATION TEST

REAGENTS USED

POSITIVE RESULT

COMPOUNDS POSITIVE FOR

THE TEST

Keller-Kiliani’s Test

FeCl3 + conc. H2SO4

REDDISH BROWN color BLUE/PURPLE

Deoxysugars

Libermann-Burchard Test

Residue in CHCl3 + acetic anhydride + conc H2SO4

IMMEDIATE COLOR CHANGE BLUE – GREEN, RED, PINK, PURPLE/VIOLET

Aglycone steroidal group

IDENTITY TESTS for CARDIAC GLYCOSIDES

IDENTIFICATION TEST

REAGENTS USED

POSITIVE RESULT

COMPOUNDS POSITIVE FOR

THE TESTKedde’s Test CHCl3 soln of

residue +Kedde’s reagent A (3,5 dinitrobenzoic acid) + Kedde’s reagent B (NaOH)

VIOLET color Unsaturated lactones