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High blood pressure, or hypertension, is a prevalent condition in the United States. One in three adults has hypertension, and approximately 20% do not know that they have it. If left untreated, high blood pressure can lead to major health issues, including stroke, heart attack, and kidney disease or failure. A number of drugs can help control hypertension, including those shown in Table 1. These drugs can be classified into different groups based on their mechanism of action.Table 1 Drugs Used to Treat High Blood Pressure
Labetalol (Figure 1) exists as four stereoisomers and is administered as a mixture of all four. This drug can be classified as a pseudohybrid drug because two of the isomers, (R,R) and (S,R) , exhibit biological activity; the other two isomers, (S,S) and (R,S) , are not active. The (R,R) isomer acts as a nonselective β-adrenergic receptor blocker, and the (S,R) isomer acts as a selective α-adrenergic receptor blocker.
Figure 1 Structure of (±) -labetalol and l-epinephrinel-epinephrine (Figure 1) is the agonist of the α- and β-adrenergic receptors. The structural motifs that allow l-epinephrine to bind to the adrenergic receptors include an amine separated from an aromatic ring by two carbon units, a hydroxyl group at a chiral center beta to the amine, and two hydroxyl groups on the aromatic ring in the meta and para positions. With a few structural modifications, the agonist l-epinephrine can be converted into the antagonist labetalol. Substitution of a hydroxyl on the aromatic ring with an amide group and extension of the methyl group on the amine transforms l-epinephrine into labetalol. These substitutions keep a majority of the structural motifs necessary for labetalol to mimic l-epinephrine and bind to the adrenergic receptors.
-The structure of eprosartan mesylate is shown below. Double bonds 1 and 2, respectively, can be classified as:

Question

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High blood pressure, or hypertension, is a prevalent condition in the United States. One in three adults has hypertension, and approximately 20% do not know that they have it. If left untreated, high blood pressure can lead to major health issues, including stroke, heart attack, and kidney disease or failure. A number of drugs can help control hypertension, including those shown in Table 1. These drugs can be classified into different groups based on their mechanism of action.Table 1 Drugs Used to Treat High Blood Pressure

Labetalol (Figure 1) exists as four stereoisomers and is administered as a mixture of all four. This drug can be classified as a pseudohybrid drug because two of the isomers, (R,R) and (S,R) , exhibit biological activity; the other two isomers, (S,S) and (R,S) , are not active. The (R,R) isomer acts as a nonselective β-adrenergic receptor blocker, and the (S,R) isomer acts as a selective α-adrenergic receptor blocker.

Figure 1 Structure of (±) -labetalol and l-epinephrinel-epinephrine (Figure 1) is the agonist of the α- and β-adrenergic receptors. The structural motifs that allow l-epinephrine to bind to the adrenergic receptors include an amine separated from an aromatic ring by two carbon units, a hydroxyl group at a chiral center beta to the amine, and two hydroxyl groups on the aromatic ring in the meta and para positions. With a few structural modifications, the agonist l-epinephrine can be converted into the antagonist labetalol. Substitution of a hydroxyl on the aromatic ring with an amide group and extension of the methyl group on the amine transforms l-epinephrine into labetalol. These substitutions keep a majority of the structural motifs necessary for labetalol to mimic l-epinephrine and bind to the adrenergic receptors.
-The structure of eprosartan mesylate is shown below. Double bonds 1 and 2, respectively, can be classified as:

Quizplus · Accepted Answer

11ecba2d_125a_fc24_a3bf_51ead29bbb28_MD0008_00 Double bonds can be classified two ways: E or Z cis or trans These isomers are special types of diastereomers in which the substituents differ in their position about a bond with restricted rotation (eg, double bond or ring). They can be di-, tri-, or tetrasubstituted. The Cahn-Ingold-Prelog priority rules are used to assign priority to the substituents on each carbon to determine whether a double bond is E or Z. Whenever the higher priority groups of each carbon are on opposite sides of the double bond, it is considered E, and it is Z when the higher priority groups are on the same side. Disubstituted double bonds are a special case in which an E bond is called trans and a Z bond is called cis. Position 1 contains a trisubstituted double bond. On the left side of the double bond, the ring is higher priority because carbon has a greater atomic number than hydrogen. The right side of the double bond is attached to two carbon atoms: a carboxyl carbon (COOH) and a carbon that is bonded to another carbon in a ring. Because oxygen has a greater atomic weight than carbon, the carboxyl group has a higher priority. Therefore, the bond is E because the high-priority groups are on opposite sides of the double bond. Position 2 is a disubstituted double bond in which both hydrogen atoms (or both high-priority groups) are on the same side; it is therefore cis. (Choices B, C, and D) For the double bond in position 2 to be trans, the hydrogen atoms (and the high-priority groups) would have to be on opposite sides of the double bond. For the double bond in position 1 to be Z, the high-priority groups would have to be on the same side of the double bond. Educational objective: E and Z designations distinguish stereoisomers about double bonds, in which Z signifies high-priority groups on the same side of the bond and E indicates the high-priority groups on opposite sides of the bond. In disubstituted double bonds, the Z conformation is also called cis and the E conformation is called trans.

Passage High Blood Pressure, or Hypertension, Is a Prevalent Condition in in the United