José Nunes da Silva Júnior

Biotransformation of the Diterpene Ent-18,19-dihydroxytrachylobane by Rhizopus stolonifer

The diterpene ent-18,19-dihydroxytrachylobane was biotransformed for the first time by Rhizopus stolonifer, and yielded the new ent-11β,18,19-trihydroxytrachylobane derivative besides the new ent-kaur-11-ene diterpenes ent-16α,18,19-trihydroxykaur-11-ene and ent-18,19-dihydroxy-16α-methoxykaur-11-ene. Their structures were determined by spectrometric methods.

New Terpenoids from Croton limae (Euphorbiaceae)

An asymmetrical dimer of kaurane diterpene and monoterpene and four novel diterpenes were isolated from the roots of Croton limae, along with kaempferol-3-O-glucoside, ombuin- 3-O-rutinoside and acetyl aleuritolic acid. The cytotoxic activity of the kaurane diterpene was evaluated against colorectal adenocarcinoma (HCT-116), ovarian carcinoma (OVCAR-8) and glioma (SF-295) cell lines, exhibiting IC50 values of 7.14, 8.19 and > 10 µg mL−1, respectively.

Ressonância: desenvolvimento, utilização e avaliação de um software educacional

that shows how electrons are shared between two or more atoms and allows a prediction of the chemical reactivity and relative stability of reagents, intermediates, and products. An educational software that enables interactive exploration of the concepts related to resonance and thereby facilitates its understanding was developed. The software was field-tested, and an evaluation questionnaire concerning the software as an educational tool was answered by the students and professors involved in the test. The results led to the conclusion that the developed computer application can be characterized as an auxiliary tool that assists teachers in their lectures and students in their learning process.

Polarímetro virtual: desenvolvimento, utilização e avaliação de um software educacional

Optical activity is the ability of chiral substances to rotate the plane of plane-polarized light and is measured using an instrument called a polarimeter. An educational software application to explore, both interactively and visually, the concepts related to polarimetry to facilitate their understanding was developed. The software was field-tested and a questionnaire evaluating the graphics interface, usability and the software as an educational tool, was answered by students. The results characterized the computer application developed as an auxiliary tool for assisting teachers in lectures and students in the learning process.

INTERACTIONS: DESIGN, IMPLEMENTATION AND EVALUATION OF A COMPUTATIONAL TOOL FOR TEACHING INTERMOLECULAR FORCES IN HIGHER EDUCATION

Intermolecular forces are a useful concept that can explain the attraction between particulate matter as well as numerous phenomena in our lives such as viscosity, solubility, drug interactions, and dyeing of fibers. However, studies show that students have difficulty understanding this important concept, which has led us to develop a free educational software in English and Portuguese. The software can be used interactively by teachers and students, thus facilitating better understanding. Professors and students, both graduate and undergraduate, were questioned about the software quality and its intuitiveness of use, facility of navigation, and pedagogical application using a Likert scale. The results led to the conclusion that the developed computer application can be characterized as an auxiliary tool to assist teachers in their lectures and students in their learning process of intermolecular forces.