1. Department of Chemistry, Korea University, Seoul, 136-701, Korea
2. The School of East-West Medical
Science, Kyung Hee University, Yongin,
446-701, Korea
3. Department
of Chemistry and Biochemistry, The University of Texas at Austin, Austin, Texas 78712-0165,
United States
4. Department
of Chemistry, Yonsei University, 262 Seonsanno
Sinchon-dong, Seodaemun-gu,
Seoul 120-749, Korea