Synthesis And Anti-osteoporosis Effects Of Novel Bone Anabolic Agents And Modification And Antiviral Activities Of Glutarimide Antibiotics

The paper comprises two parts:PART 1:Synthesis and Anti-osteoporosis Effects of Novel Bone Anabolic Agents.Most clinically used anti-osteoporosis drugs are antiresorptive agents.It's very necessary to develop anabolic agent.With the help of an anti-osteoporosis screening model targeting the promoter of the BMP-2 gene,we have evaluated thousands of compounds and observed that 1-(benzo[b]thiophen-2-yl)ethanone(G39) has potent activities in enhancing BMP-2 expression,and reduced bone defects induced by ovariectomy in OVX rat model.The TD₅₀ of compound G39 on mice was over 5g/kg (orally).The present work designed and synthesized 48 derivates of benzo[b]thiophen and benzofuran,33 of which are novel compounds.The activities of 48 derivates and other 23 compounds in enhancing BMP-2 expression were evaluated with lovastatin as a positive control using recombinant plasmid PMB and rat skull cells MC3T3-E1.At the concentration 10-fold higher than that of the positive control,lovastatin,there were 2 compounds with a upregulation rate value of more than 200%,14 compounds between 150-200%,12 compounds between 120-150%,31 compounds between 100-120%and 20 compounds below 100%.SAR(Structure-activity relationship) indicated that the benzo[b]thiophene compounds whoes benzene substituted with carboxylate or alkoxyl showed much higher upregulating rate of BMP-2,especially the 5-,6- substituents.The benzene substituted with methoxy group increased the activities of 2-carboxylate-benzofuran compounds.According to the upregulation rate in vitro and the structure features,compounds 8b,3c and S25 were chosen to investigate the anti-osteoporosis effects in SAMP6 (Senescence-accellerated mouse,strain6) mice with G39.In previous work,G39 was tested in overiectomized Sprague-Dawley rat model(OVX) to observe the effects on bone loss among postmenopausal women,then observe its effects in senile people.The results in vivo demonstrated that several compounds showed anti-osteoporosis activities at different levels.8b was the most potent derivate which increased the total BMD(bone mineral density) in SAMP6 mice,upregulated the expression of BMP-2,built up the bone mass and increased the osteocalcin in blood plasma.Pathological section of organs did not show any toxicity induced by these compounds.A preliminary test proved that mice were well tolerated with S25,3c and 8b at the doses 500mg/kg,700mg/kg and 500mg/kg,respectively.PART 2:Modification and Antiviral Activities of Glutarimide Antibiotics.It's reported that the glutarimide antibiotics S632A and Cycloheximide(CHX) inhibited many viruses.But both anibiotics were toxic and S632A is oil which isn't suitable for pharmaceutical administration.The present work modified the two antibiotics and test the anti-viral activities of the derivates.Hydrogenization the conjugated double bond of S632A and substitution of N atom of S632A afforded S522,S425 and S525.However,these derivates of S632A lost anti-viral activities.The six-membered glutarimide ring was opened in base enviroment which led the salification of S632A a failure.Protection of the hydroxy and reduction of carbonyl group of S632A were failed because of the instability of the structure.Dehydration always happened first during the modification of the structure of CHX and two dehydrating products,1a and 1b,were got.1a and 1b were separated by medium pressure liquid chromatography.The stereo structure of 1a was determined by X-ray diffraction,in which C-3" was found to be R,and the double bond between C-2' and C-1" was the E configuration.CD spectra of 1a and 1b were acquired.Based on other spectrum information and the CD spectra,1b was found the epimer of 1a.1a and 1b lost the inhibiting activities against HIV,HSV and influenza.But both of 1a and 1b showed much stronger anti-HBV activities(over 20 fold higher) and higher selective indexes than CHX.Alkylation of nitrogen atom in glutarimide ring of 1a,and reduction of cyclohexanone ring of 1a made anti-HBV activity disappeared.The work of part 2 produced 13 compounds and 6 were new,the absolute configurations of 2 known compounds were determined for the first time.