Ocotillol(OT)-type ginsenosides,one subtype of ginsenosides,consist of a dammarane skeleton and a tetrahydrofuran ring.Most naturally-occurring OT-type ginsenosides exist in Panax species,particularly in Panax quinque...Ocotillol(OT)-type ginsenosides,one subtype of ginsenosides,consist of a dammarane skeleton and a tetrahydrofuran ring.Most naturally-occurring OT-type ginsenosides exist in Panax species,particularly in Panax quinquefolius,which may be attributed to the warm and humid climate of its native areas.Till now,merely 28 types of naturally-occurring OT-type ginsenosides have been isolated.In contrast,semi-synthesized OT-type ginsenosides are attracted considerable attentions.These ginsenosides can be obtained through oxidation and cyclization of side chains of dammarane-type ginsenosides,and other methods,which may change their physical and chemical properties and further improve their bioavailabilities.It is also notable that the pharmacological activities of ginsenosides are closely related to the stereoisomers caused by the configuration at C-20.Semi-synthesis of OT-type ginsenosides can facilitate our understanding of the biosynthesis,transformation and metabolism of OT-type ginsenosides in the body.This review will systematically summarize the research progress on naturally-occurring and semi-synthetic OT-type ginsenosides,which provides a theoretical basis for their bioactivity-guided research.展开更多
In this paper, the fully anisotropicoverall tumbling motions and side groups internal rotation of ocotillol-type saponins separated from the leaves of Panax Quidquefolium L. are investigated by ^(13)C nuclear magnetic...In this paper, the fully anisotropicoverall tumbling motions and side groups internal rotation of ocotillol-type saponins separated from the leaves of Panax Quidquefolium L. are investigated by ^(13)C nuclear magnetic relaxation. The fully anisotropic overall tumbling motion model with methyl conformation jumps internal rotation among three equivalent sites is presented, and the spectral density function of this model is derived. The rotation rates for overall tumbling motions to ocotillol-type saponins (OTS) are computed by Woessner's fully anisotropic overall tumbling motion model, and the internal rotation rate and barrier for side groups in OTS are calculated using free diffusion internal rotation model, restriction diffusion internal rotation model and conformation jumps internal rotation model, respectively.展开更多
基金supported by the National Key R&D Program of China(No.2017YFC1702302)。
文摘Ocotillol(OT)-type ginsenosides,one subtype of ginsenosides,consist of a dammarane skeleton and a tetrahydrofuran ring.Most naturally-occurring OT-type ginsenosides exist in Panax species,particularly in Panax quinquefolius,which may be attributed to the warm and humid climate of its native areas.Till now,merely 28 types of naturally-occurring OT-type ginsenosides have been isolated.In contrast,semi-synthesized OT-type ginsenosides are attracted considerable attentions.These ginsenosides can be obtained through oxidation and cyclization of side chains of dammarane-type ginsenosides,and other methods,which may change their physical and chemical properties and further improve their bioavailabilities.It is also notable that the pharmacological activities of ginsenosides are closely related to the stereoisomers caused by the configuration at C-20.Semi-synthesis of OT-type ginsenosides can facilitate our understanding of the biosynthesis,transformation and metabolism of OT-type ginsenosides in the body.This review will systematically summarize the research progress on naturally-occurring and semi-synthetic OT-type ginsenosides,which provides a theoretical basis for their bioactivity-guided research.
基金Project supported by the National Natural Science Foundation of China and the State Key Laboratory of Applied Organic Chemistry, Lanzhou University.
文摘In this paper, the fully anisotropicoverall tumbling motions and side groups internal rotation of ocotillol-type saponins separated from the leaves of Panax Quidquefolium L. are investigated by ^(13)C nuclear magnetic relaxation. The fully anisotropic overall tumbling motion model with methyl conformation jumps internal rotation among three equivalent sites is presented, and the spectral density function of this model is derived. The rotation rates for overall tumbling motions to ocotillol-type saponins (OTS) are computed by Woessner's fully anisotropic overall tumbling motion model, and the internal rotation rate and barrier for side groups in OTS are calculated using free diffusion internal rotation model, restriction diffusion internal rotation model and conformation jumps internal rotation model, respectively.
