1. Department of Chemistry, University of Nairobi, P.O. Box 30197-00100, Nairobi,
Kenya
2. Department of Chemistry
and
Molecular Biology, University of Gothenburg, SE-412 96 Gothenburg, Sweden
3. Swedish NMR Centre, University of Gothenburg, P.O. Box 465, SE-40530 Gothenburg,
Sweden
4. United States Army Medical Research Unit-Kenya, MRU 64109, APO, AE 09831-4109,
United States