@article{vieira_takahashi_oliveira_chiari_boaventura_2002,  title={Novel Derivatives of Kaurenoic Acid},  volume={13},  ISSN={0103-5053},  url={https://doi.org/10.1590/S0103-50532002000200004},  DOI={10.1590/S0103-50532002000200004},  number={2},  journal={Journal of the Brazilian Chemical Society},  publisher={Sociedade Brasileira de Química},  author={Vieira, Henriete S. and Takahashi, Jacqueline A. and Oliveira, Alaíde B. de and Chiari, Egler and Boaventura, Maria Amélia D.},  year={2002},  pages={151–157} }