Organic Chemistry of Drug Synthesis. Volume 7

N

(C 6 H 5 ) 3 C N CO 2 H (C 6 H 5 ) 3 C

(C 6 H 5 ) 3 C

(C 6 H 5 ) 3 C

(C 6 H 5 ) 3 C

N

N

H

N

N CH=O

H

N

N

CF 3 SO 2 H

N N BuLI

H

N

HN

H

HCl

86 87 88

89

90

92 91

O 2 S

N

O DIBAL-H

(CH 3 )SiCHN 2

BuLi

The three part so-called cocktail used to treat HIV positive patients
typically comprise a proteinase inhibitor, such as those discussed in
Chapter 1; a nucleoside-based reverse transcriptase inhibitor, such as those
in Chapter 6, and a non-nucleoside inhibitor of reverse transcriptase
(NNRTI). Most of the compounds in the first two classes share a good
many structural features with other agents in the class. Chemical structures
of the various NNRTIs on the other hand have little in common.
Capravirine( 103 ), is notable in the fact that it fails to include any of
the fused ring systems that provide the nucleus for other compounds in
this class. Chlorination of 3-methylbutyraldehyde ( 94 ) provides one of
the components for building the imidazole ring. For bookkeeping pur-
poses, the condensation of 94 withO-benzyl glyoxal and ammonia can be

R

R + O

OCH 2 C 6 H 5

O

Cl

Cl NH 2

OH 2 N OCH 2 C 6 H 5

93 ; R = H

94 ; R = Cl

95

NH 4 OH

N

HN

OCH 2 C 6 H 5

96

N

HN

OCH 2 C 6 H 5

97

I 2 , NaOH

I

Cl

Cl

Cl S–

N Cl 2

HN

OCH 2 C 6 H 5

98

S

99

N

N

Cl

100

Cl

Cl

N

N

OCH 2 C 6 H 5

S

101

HCl N

Cl

Cl

N

N

S OH

102

94

ClSO 2 N=C=O

N

Cl

Cl

N

S N

103

O NH 2

O

2. COMPOUNDS WITH TWO HETEROATOMS 95