海风藤化学成分及其抗菌活性和抗冠状病毒活性研究

Chemical constituents and antibacterial,anti-coronavirus activities of Piperis Kadsurae Caulis

目的研究海风藤(风藤Piperis kadsurae干燥藤茎)的化学成分,对其抗菌及抗冠状病毒进行活性评价。方法利用硅胶、Sephadex LH-20、MCI柱色谱以及半制备高效液相色谱等进行分离纯化,并运用NMR、HR-ESI-MS等技术对化合物进行结构鉴定。采用梯度稀释法,对分离所得的化合物进行抗蜡样芽胞杆菌、金黄色葡萄球菌以及耐甲氧西林金黄色球菌(MRSA)的活性评价,初步探讨了所分离化合物对SARS-CoV-2主蛋白酶(main protease,Mpro)的抑制活性。结果从海风藤醋酸乙酯萃取部位分离得到16个化合物,分别鉴定trans-2-methoxy-4.5-methylenedioxy-cinnamoy1-piperidide(1)、cis-2-methoxy-4.5-methylenedioxy-cinnamoy1-piperidide(2)、3-(4,7-dimethoxy-1,3-benzodioxol-5-yl)-1-(1-piperidinyl)-2-propen-1-one(3)、4-[5-[(1E)-3-hydroxy-1-propen-1-yl]-7-methoxy-3-methyl-2-benzofuranyl]-2-methoxyphenol(4)、methyl(2E,4E)-5-(4-hydroxy-3-methoxyphenyl)-2,4-pentadienoate(5)、胡椒酸(6)、辛夷脂素(7)、denudatin B(8)、l-cinnamoylpyrrolidine(9)、假蒟亭碱(10)、胡椒碱(11)、胡椒新碱(12)、(E,E)-N-isobutyl-2,4-octadienamide(13)、4-allylbenzene-1,2-diol(14)、rabdosia acid A(15)、白桦脂酸(16)。与阳性对照药万古霉素相比,化合物1~2、4~10、12~16均具有显著的抗菌活性,其中,化合物1、5、6、10、12和15对金黄色葡萄球菌的最低抑菌浓度(minimum inhibitory concentration,MIC)值均为0.78μg/mL,化合物1~2、8~9、12和14对MRSA的MIC值均为3.12μg/mL。同时,与阳性抑制剂(Ebselen)相比,化合物2~4、8、11~12、14、16具有潜在的抗冠状病毒活性,半数抑制浓度(median inhibition concentration,IC_(50))为4~7μmol/L。结论化合物1~6为首次分离得到的天然产物,并首次提供化合物1~5的核磁数据;化合物15和16为首次从胡椒科植物中分离得到;化合物7、9~12、14为首次从海风藤植物中分离得到;化合物2、8、12在抗菌及抗冠状病毒方面均有较为显著的药理活性,可为后续研究和开发相关新药提供科学依据。

Objective To study the chemical constituents of the Haifengteng(Piperis Kadsurae Caulis)(dried vine stems of P.kadsurae)and evaluate their antibacterial and anti-coronavirus activities.Methods The compounds were isolated and purified by silica gel,Sephadex LH-20,MCI column chromatography and semi-preparative high performance liquid chromatography,and their structures were identified by NMR and HR-ESI-MS and other spectral techniques.The activity of the isolated compounds against Bacillus cereus,Staphylococcus aureus and methicillin-resistant Staphylococcus aureus(MRSA)was evaluated by gradient dilution method.In addition,the inhibitory activity of the isolated compounds against SARS-CoV-2 main protease(Mpro)was preliminarily evaluated.Results A total of sixteen compounds were isolated and identified as trans-2-methoxy-4.5-methylenedioxy-cinnamoy1-piperidide(1),cis-2-methoxy-4.5-methylenedioxy-cinnamoy1-piperidide(2),3-(4,7-dimethoxy-1,3-benzodioxol-5-yl)-1-(1-piperidinyl)-2-propen-1-one(3),4-[5-[(1E)-3-hydroxy-1-propen-1-yl]-7-methoxy-3-methyl-2-benzofuranyl]-2-methoxyphenol(4),methyl(2E,4E)-5-(4-hydroxy-3-methoxyphenyl)-2,4-pentadienoate(5),piperic acid(6),fargesin(7),denudatin B(8),1-cinnamoylpyrrolidine(9),sarmentine(10),piperine(11),piperanine(12),(E,E)-N-isobutyl-2,4-octadienamide(13),4-allylbenzene-1,2-diol(14),rabdosia acid A(15),betulinic acid(16).Compared with the positive control vancomycin,compounds 1—2、4—10、12—16 had significant antibacterial activity.The minimum inhibitory concentration(MIC)values of compounds 1,5,6,10,12 and 15 against Staphylococcus aureus were 0.78μg/mL,and the MIC values of compounds 1—2、8—9、12 and 14 against MRSA were 3.12μg/mL.At the same time,compounds 2—4,8,11—12,14 and 16 showed potential anti-coronavirus activity with median inhibition concentration(IC_(50))values ranging from 4—7μmol/L.Conclusion Compounds 1—6 were the natural products isolated for the first time,and the NMR data of compounds 1—5 were provided firstly in our study.Compounds 15 and 16 were isolated from Piperaceae for the first time.Compounds 7,9—12 and 14 were isolated firstly from Piperis Kadsurae Caulis.Compounds 2,8 and 12 had significant antibacterial and anti-coronavirus activities,which could provide scientific basis for subsequent research and development of related new drugs.