Antifouling Activity of Simple Synthetic Isocyanides Against Larvae of the Barnacle Balanus amphitrite

Abstract

Twelve simple linear isocyanides were synthesized and examined for antifouling activity and toxicity against cyprid larvae of the barnacle, Balanus amphitrite. Larval settlement was inhibited, with EC₅₀ values of 0.046 – 1.90 μg ml⁻¹, and they were much less toxic (LD₅₀ values ranging over 21.28 μg ml⁻¹) than CuSO₄ (EC₅₀ 0.30 μg ml⁻¹ and LD₅₀ 2.95 μg ml⁻¹). The data indicate that simple linear isocyanides are promising non-toxic antifouling agents.

Keywords:

• antifoulant
• barnacle
• isocyanide
• natural product
• cyprid larvae
• Balanus amphitrite

Acknowledgements

We thank Prof N Fusetani of the University of Tokyo for valuable discussions. Thanks are also to Dr K Okamoto of the University of Tokyo and T Ookawara of Maisaka oyster cultivation union of Lake Hamana for their help in collecting barnacles.