PRELIM 03 - Stereochemistry

Question 1

Refers to the three-dimensional orientation of the functional groups present in a molecule

Answer 1

Sterochemistry

Question 2

__________ are molecules that contain the same number and kinds of atoms, the same arrangement of bonds, but different three-dimensional structures

Answer 2

Stereoisomers

Question 3

2 types of stereoisomers (ED)

Answer 3

Enantiomers, Diastereomers

Question 4

Are pairs of molecules for which the three-dimensional arrangement of atoms represents nonsuperimposable mirror images (Types of stereoisomers)

Answer 4

Enantiomers

Question 5

Represents all of the other stereoisomeric compounds that are not enantiomers (Types of stereoisomers)

Answer 5

Diastereomers

Question 6

__________ includes compounds that contain double bonds and ring systems (Types of stereoisomers)

Answer 6

Diastereomers

Question 7

Exhibit different physicochemical properties, including melting point, boiling point, solubility, and chromatographic behavior (Types of stereoisomers)

Answer 7

Diastereomers

Question 8

Rotates the plane of polarized light to the right, or in a clockwise direction; indicated by a (+) sign

Answer 8

Dextrorotatory

Question 9

Rotates the plane of polarized light to the left, or in a counterclockwise direction; indicated by a (-) sign

Answer 9

Levorotatory

Question 10

Dextroamphetamine, dextromethorphan, and dexlansoprazole are all __________

Answer 10

Dextrorotatory

Question 11

Levodopa, levothyroxine, and levofloxacin are all __________

Answer 11

Levorotatory

Question 12

Most sugars found in nature (ex: D-glyceraldehyde, D-glucose) are __________

Answer 12

Dextrorotatory

Question 13

Most amino acids found in nature (ex: L-serine, L-alanine) are __________

Answer 13

Levorotatory

Question 14

A mixture comprised of equal amounts (1:1 mixture) of both of the possible drug enantiomers; indicated by the placement of a (±) sign before the compound name

Answer 14

Racemic mixture (Racemate)

Question 15

A new system of stereochemical nomenclature; uses the R-S and cis-trans configuration

Answer 15

Cahn-Ingold-Prelog (CIP) system

Question 16

Priority sequence proceeds to the right, or in a clockwise direction (Configuration in CIP system)

Answer 16

R-configuration

Question 17

Priority sequence proceeds to the left, or in a counterclockwise direction (Configuration in CIP system)

Answer 17

S-configuration

Question 18

Inactive configuration of ibuprofen

Answer 18

R-ibuprofen

Question 19

Active configuration of ibuprofen; possesses anti-inflammatory effect

Answer 19

S-ibuprofen

Question 20

The R-enantiomer of Modafinil (a racemic mixture)

Answer 20

Armodafinil

Question 21

The S-enantiomer of Omeprazole (a racemic mixture)

Answer 21

Esomeprazole

Question 22

When two substituents of higher priority are on the same size of the double bond (Configuration in CIP system)

Answer 22

Cis (Z-isomer)

Question 23

When two substituents of higher priority are on the opposite sides of the double bond (Configuration in CIP system)

Answer 23

Trans (E-isomer)

Question 24

__________-diethylstilbestrol is estrogenic, whereas cis-diethylstilbestrol is only 7% as active

Answer 24

Trans

Question 25

Trans-diethylstilbestrol is estrogenic, whereas __________-diethylstilbestrol is only 7% as active

Answer 25

Cis

Question 26

Inactive configuration of triprolidine

Answer 26

Z-triprolidine

Question 27

Active configuration of triprolidine

Answer 27

E-triprolidine

Question 28

____________ refers to a preference for one stereoisomer as a substrate for a metabolizing enzyme; may lead to differences in metabolism for the two enantiomers

Answer 28

Substrate stereoselectivity

Question 29

(+) enantiomer of __________ undergoes more rapid metabolism than the corresponding (-) enantiomer; this is an example of substrate stereoselectivity

Answer 29

Propranolol

Question 30

__________ refers to the preferential metabolic formation of a stereoisomeric product

Answer 30

Product selectivity

Question 31

In humans, __________ is metabolized predominantly to the trans alcohol, whereas rats primarily tend to form the cis alcohol; this is an example of product selectivity

Answer 31

Pentazocin

Question 32

__________ refers to the selective metabolism of two or more similar functional groups that are positioned in different regions of a molecule

Answer 32

Regioselectivity

Question 33

Of the four methoxy groups present in __________, the 4-OCH3 group is regioselectively O-demethylated in several species; this is an example of regioselectivity

Answer 33

Papaverine