Oral contraceptive - Anderson Flashcards
name of the oral contraceptive we study
norethindrone
what is norethindrone an analogue of
progesterone
what structure do steroids usually have
C17 tetracyclical fused ring system
planar
examples of other steroids
cholesterol, testosterone and oestrogen
how many chiral centres do steroids have
many
chemical formula of progesterone
C21H30O2
how many stereogenic centres does progesterone have
14
how many women worldwide use the pill
100 million
how many women age 19-49 take the pill
1/3
when was norethindrone first marketed
1961
other name for oestrogen
estradiol
when is increase and decrease in estradiol
increases first part of cycle
decreases before ovulation
what triggers lutenising hormone
drop off of oestrogen
which hormones cause ovulation
LH and FSH - lutenising and follicle stimulating hormone
how does oral contraceptive work
constant level of hormones mimic pregnancy so LH and FSH not released
how does progesterone prevent pregnancy
creates a thick layer of cervical mucus which sperm cannot penetrate
produce a thinner endometrium so eggs cannot implant
how successful is oral contraceptive
99.9%
steps 1-2 synthesising norethodrone
synthesis of a methyl ether
steps 2-3 of synthesising norethodrone
birch reduction
aromatic ring to diene
makes enol ether which is protected form of a ketone
steps 3-4 of synthesising norethindrone
oxidation of a secondary alcohol to form a ketone
using PCC under dry conditions
steps 4-5 synthesis of norethindrone
addition of a metal-acetylide to a ketone
stereoselective
steps 5-6 of synthesis of norethindrone
hydrolysis of the enol ether
synthesis of norethindrone steps 6-7
migration of a double bond
how was the combined pill invented
residues of menstranol (analogue of estradiol) from previous steps found to be more effective