A new degraded sesquiterpene was isolated from the marine actinomycete Streptomyces sp. 0616208. Its structure was elucidated as (1α; 4aα; 5α, 7β, 8aβ)-5, 8a-dimethyl-decahydrona- phthalene-1, 4a, 7-triol on th...A new degraded sesquiterpene was isolated from the marine actinomycete Streptomyces sp. 0616208. Its structure was elucidated as (1α; 4aα; 5α, 7β, 8aβ)-5, 8a-dimethyl-decahydrona- phthalene-1, 4a, 7-triol on the basis of spectroscopic data.展开更多
Synthesis of telechelic trans-1,4-polyisoprenes(TPI: trans-structure > 95%) was evaluated based on two different methods of oxidative cleavage(indirect cleavage: first epoxidation of TPI, then the selective c...Synthesis of telechelic trans-1,4-polyisoprenes(TPI: trans-structure > 95%) was evaluated based on two different methods of oxidative cleavage(indirect cleavage: first epoxidation of TPI, then the selective cleavage of epoxidized units in epoxidized trans-1,4-polyisoprene(ETPI) and direct cleavage of isoprene units in TPI). The influence of solvents and the ratio of oxidative agents was investigated by 1H-NMR and 13C-NMR. A series of well-defined telechelic TPI with double terminated functional groups and less side reaction(molecular weight distribution range: 1.96?2.26) were synthesized by indirect cleavage in chloroform. Telechelic TPI showed similar crystallization behavior with TPI and interesting cold crystallization behavior characterized by DSC.展开更多
文摘A new degraded sesquiterpene was isolated from the marine actinomycete Streptomyces sp. 0616208. Its structure was elucidated as (1α; 4aα; 5α, 7β, 8aβ)-5, 8a-dimethyl-decahydrona- phthalene-1, 4a, 7-triol on the basis of spectroscopic data.
基金financially supported by the Natural Science Foundation of Shandong Province(No.ZR2014BQ022)the National Natural Science Foundation of China(No.51273100)a Project of Shandong Province Higher Educational Science and Technology Program(No.J14LA12)
文摘Synthesis of telechelic trans-1,4-polyisoprenes(TPI: trans-structure > 95%) was evaluated based on two different methods of oxidative cleavage(indirect cleavage: first epoxidation of TPI, then the selective cleavage of epoxidized units in epoxidized trans-1,4-polyisoprene(ETPI) and direct cleavage of isoprene units in TPI). The influence of solvents and the ratio of oxidative agents was investigated by 1H-NMR and 13C-NMR. A series of well-defined telechelic TPI with double terminated functional groups and less side reaction(molecular weight distribution range: 1.96?2.26) were synthesized by indirect cleavage in chloroform. Telechelic TPI showed similar crystallization behavior with TPI and interesting cold crystallization behavior characterized by DSC.