Two novel taxoids were synthesized from 1-deoxybaccatin Ⅵ and their crystal structures were determined by X-ray crystallographic techniques. The influences of oxetane ring on molecular conformations and bioactivity w...Two novel taxoids were synthesized from 1-deoxybaccatin Ⅵ and their crystal structures were determined by X-ray crystallographic techniques. The influences of oxetane ring on molecular conformations and bioactivity were investigated. The result shows that the oxetane ring plays an important role in the conformation and bioactivity of the diterpenoid core. In the structure of compound 3, the six-membered A ring exhibits the 1,4-di-planar conformation, the eightmembered B ring adopts a boat-chair conformation, and the six-membered C ring exhibits a slightly distorted half-chair conformation. However, in D-seco-taxoid 4, the six-membered C ring exhibits a boat conformation with the release of ring strain for the D-ring opening.展开更多
Three C-3’-N-sulfonyl and C-7-O-acyl paclitaxel analogues were synthesized from 10-deacetyl baccatinⅢ(10-DAB)and their structures were confirmed by 1H NMR,13C NMR and HR-MS.Among them,the crystal structure of compou...Three C-3’-N-sulfonyl and C-7-O-acyl paclitaxel analogues were synthesized from 10-deacetyl baccatinⅢ(10-DAB)and their structures were confirmed by 1H NMR,13C NMR and HR-MS.Among them,the crystal structure of compound 9 b was determined by single-crystal X-ray diffraction.Compound 9 b crystallizes in monoclinic system,space group P21 with a=12.395(4),b=15.215(5),c=14.905(5)A,β=105.559(4)°and Z=2.In the structure,the introduction of the hydrophobic 3-fluorobenzoyl group at C(7)has little effect on the conformation of tetracyclic system.However,the conformation of the side-chain at C(13)in 9 b is quite different from that of paclitaxel and docetaxel.展开更多
基金supported by the National Natural Science Foundation of China(No.21272154 and 81202402)
文摘Two novel taxoids were synthesized from 1-deoxybaccatin Ⅵ and their crystal structures were determined by X-ray crystallographic techniques. The influences of oxetane ring on molecular conformations and bioactivity were investigated. The result shows that the oxetane ring plays an important role in the conformation and bioactivity of the diterpenoid core. In the structure of compound 3, the six-membered A ring exhibits the 1,4-di-planar conformation, the eightmembered B ring adopts a boat-chair conformation, and the six-membered C ring exhibits a slightly distorted half-chair conformation. However, in D-seco-taxoid 4, the six-membered C ring exhibits a boat conformation with the release of ring strain for the D-ring opening.
基金supported by the National Natural Science Foundation of China(Nos.21272154 and 81202402)。
文摘Three C-3’-N-sulfonyl and C-7-O-acyl paclitaxel analogues were synthesized from 10-deacetyl baccatinⅢ(10-DAB)and their structures were confirmed by 1H NMR,13C NMR and HR-MS.Among them,the crystal structure of compound 9 b was determined by single-crystal X-ray diffraction.Compound 9 b crystallizes in monoclinic system,space group P21 with a=12.395(4),b=15.215(5),c=14.905(5)A,β=105.559(4)°and Z=2.In the structure,the introduction of the hydrophobic 3-fluorobenzoyl group at C(7)has little effect on the conformation of tetracyclic system.However,the conformation of the side-chain at C(13)in 9 b is quite different from that of paclitaxel and docetaxel.
