Synthesis of Novel Oxazolyl-indoles

Abstract

We describe the synthesis of oxazolyl-indoles that are structurally related to pimprinaphine. The effect of the indole N-cyanoalkyl substituents on the 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) mediated oxidation was evaluated.

Key words

oxazolyl-indoles - Yonemitsu reaction - DDQ-mediated oxidation - cyclizations - coupling

References

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Murine spleen cells were cultured at 37 °C for 72 h in the presence or absence of oxazole 9 and the proliferation was measured by incorporation of [3H]. Results are expressed as stimulation indices (SIs; SI = mean cpm for stimulated sample/mean cpm for unstimulated sample). The stimulation indices were 1.1, 1.3 and 1.4 when measured for concentrations of 2, 4 and 8 nM, respectively. Additional work is underway to determine whether the stimulatory effect of 9 is associated with Th1/Th2 cytokine production by T cells.

21

CAUTION: The compound is a severe skin irritant, not unlike α-chloroacetophenone (the tear gas ‘CN’ or ‘Mace’).