Scheme 2.

Synthesis of 4-(3-(hydroxymethyl)-4-nitrophenoxy) butanoic acid and 4-(3-(1-hydroxyethyl)-4-nitrophenoxy) butanoic acid.

Synthesis of 4-(3-(hydroxymethyl)-4-nitrophenoxy) butanoic acid and 4-(3-(1-hydroxyethyl)-4-nitrophenoxy) butanoic acid.