21'ALFA'-Fluoro-7-norvouacapane-17'BETA',21'ALFA'-lactone - Ruggiero, Silvana Guilardi; Gambardella, Maria Teresa do Prado; Branco, Marcelo Cardoso; Demuner, Antonio Jacinto; Barbosa, Luis Carlos A.; Piló-Veloso, Dorila (Acta Crystallographica. Section C, 2000)