Figure 3

Derivatizations of analytes prior to GC-MS analysis. (A) IPA is first reduced by NaB²H₄ to yield ² H₁ILA (Steps 5–6). ² H₁ILA is then methylated by diazomethane to form methyl-² H₁ILA (Step 20). (B) IAA and (C) IBA are methylated by diazomethane and yield methyl-IAA and methyl-IBA (Step 50). (D) Trp is derivatized by methyl chloroformate (MCF) in the presence of methanol and pyridine (Steps 60–61). Carbon atoms from both MCF and methanol are incorporated into the final product. The “*” and “#” labels mark the flow of these carbons [30].