| 1-organic nitrates & nitrites | mech & drug interactions | Nicardipine | 1,4 -dihydro-2,6-dimethyl -4-(3-nitrophenyl) -3,5- pyridine dicarboxylic acid methyl 2-[methyl-(phenylmethyl) amine] ethyl ester *uses more potent vasculature ,used in ttt of mild ,moderate ,severe hypertension & stable angina *subst >m position |
| Amyl nitrite (isopentyl nitrate) | *mix of isomeric amyl nitrites *prep from amyl alc + nitrous acid *dispensed in ampul form and used by inhalatn orally in alc soln *onset is half min , dures for 1 min *ttt of CN poison | ||
| Nitroglycerin (glyceryl trinitrate) | *dispensed in sublingual tablets & transdermal prep *onset 2min ,duers for half an hour (syn) | Felodipine | *2nd generation used in ttt of angina & hypertension *syn from methyl aceto acetate + EAA + NH3 *o,m subst |
| diluted Erythrityl tetranitrate (cardilate) | *1,2,3,4 butanetetrol tetranitrate *ester of erythritol & nitric a *onset 15 min ,duration 3 h' *diluted by lactose ,mannitol or suitable excipient to enable safe handling (nitro >explosive) | B) benzothiazepine :: Diltiazem | (+) cis-3-acetoxy-5-[2-(dimethylamino)ethyl]-2,3-dihdro-2-(4-methoxyphenyl)-1,5-benzothiazepin-4(5H)one HCl *it + myocardial O2 supply by relieving coronary spasm & ! Myocardial O2 demand by ! HR & ! Overload *uses :1-ttt of angina pectoris 2-ttt arrythmias from ischemic myocardial syndrome **metab >only give active metabolite |
| dilyted pentaerythritol tetranitrate | 2,2-Bis(hydroxymethyl) -1,3-propanediol tetranitrate *onset 20 m' ,duration 5.5h' | C)phenyl alkyl amine :: Verapamil | *2 isopropyl valeronitrile drv *metab >N-demethylatn >nor verapamil (inactive) *used in ttt of angina pectoris & arrythmia *contain chiral c & levoisomer is most potent |
| diluted isosorbride dinitrate (Isordil) | 1,4:3,6 -dianhydro-D-glucitol dinitrate *used in ttt & prophylaxis of acute anginal attacks in form of sublingual or chewable tablets (in acute attacks onset 2m')or oarl tablets (ttt of angina onset 15-30 m') *stereochemistry is important (2 exo ,5 endo >cpd active ,,, endo -endo >inactive ,, exo-exo >active but not used ) *5- isomer is still vasodilator & its plasma halflife is 4-5 h' w is longer than isosorbide dinitrate itself ,the extended t1/2 owing to metabolites ,resistance to other metab *syn & metab > | 3-miscellaneous :: Nicotinyl alcohol tartarate (Roniacol) | 3-pyridine methanol tartarate *drug converted in body to nicotinic acid *it has direct relaxing effect on peri BV *used in vascular spasm ,Raynaud's syndrome (tartarate salt) |
| 2- Ca channel blockers | VD of tissuse e subsequent ! HR ! Myocardial contractility affect myocardium conraction & vascular s.m *also used as antihypertensive | Dipyridamole (persantine) >chemical name !!!!!!!!!!!!! | *inhibit adenosine deaminase in erythrocytes and interfere e the uptake of vasodilator adenosine by erythrocytes *some structure similarity of adenosine to dipyridamole is apparent and *used prophylactically to reduce incidence of anginal attacks |
| A) Dihydropyridine drv | SAR > | ||
| Nifedipine | 1,4-dihydro -2,6-dimethyl -4- (2-nitrophenyl) -3,5-pyridine dicarboxylate dimethyl ester *syn > Hanzsch Rx *metab (cyp3A4) dihydro pyridine >pyridine (active) *inhibit Ca dependent channel in vascular s.m than in cardiac muscle | Cyclandelate (cyclospasmol) | 3,5,5-trimethyl cyclohexyl mandelate *produce peri VD by acting on s.m |
| Amlodipine | 3,5-pyridine dicarboxylic acid -2[(2-aminoethoxy) methyl]-4- (2-chlorophenyl) 1,4-dihydro-6-methyl -3-ethyl -5-methyl ester *it is 2nd generatn of DHP drv *more selective for vascular s.m than myocardial tissue *longer half life (34h') *used in ttt of stable chronic angina & management of mild hypertension | Bepridil (Vascor) | *it block slow Ca channels & block Na channels > ! Cardiac contractn *used only if patient is tolerated to other antianginal |