Study On The Synthesis Of Deoxycholic Acid Amide And Nitrogenous Compounds

In recent years, a variety of steroids with unusual and interesting structures, such as polyhydroxyl sterols, steroidal oximes and steroidal hydrazone compounds, have been isolated from marine organisms. Many of them exhibit antineoplastic, antivirus and antiphlogistic activities. However, because the contents of these compounds are very small in living body, they can be applied widely only by the synthetic methods. At the same time, it was found in the study of these steroids that some compounds, when the N, O, S and other miscellaneous atoms or some functional groups with these miscellaneous atoms were connected to the steroid nucleus or its side chain, may give a unique bioactivity.Therefore, taking some natural steroids with anti-tumor activity as a reference, and combining with a preliminary study of our research group, we designed and synthesized a series of nitrogen-containing steroids. It is hoped to find to several active drugs with clinical value in anti-tumor.Using natural and obtainable bile acid, cholesterol, pregnant sterols as starting materials, twenty-four steroids with different structures were synthesized (Twenty of them are new compounds).The structures of products were identified by IR, 1H NMR, 13C NMR and MS.Firstly, according to the results of preliminary studies of our group and using cholesterol as a starting material, the 3β-acetoxycholest-5-en-7-one was prepared by acetylation and oxidation of chromium trioxide. And then five compounds of 3-hydroxycholest-5-ene which were substituted in the 7-position of the steroid nucleus by functional groups with nitrogen were synthesized by the conversion of functional groups and deacetylating. In addition, cholesterol-4-en-3, 6–dione was obtained by PPC oxidation using cholesterol as a material, then it can be reduced to 3β-hydroxycholest-6-one using NaBH4 as reductive agent under the presence of Ni2+. Then a series of 3-hydroxycholestane compounds were obtained through the transformation of 6-carbonyl group. They are 3β-hydroxycholest-6-thiosemicarbazone, 3β-hydroxycholest-6-semicarbazone, 3β-hydroxycholest-6-methoxyoxime, 3β-hydrox - ycholest-6-benzyloxyoxime. Using cholest-4-en-3, 6-dione as a starting material, cholest-3, 6-dione was obtained by selective reduction. Then through the transformation of 3-carbonyl group and the reduction of 6-carbonyl, six compounds were obtained. They are cholest-6–oxy-3-thiosemicarbazone, cholest-6-oxy-3- methoxyoxime, cholest-6-oxy-3-benzyloxyoxime, 6-hydroxycholest-3-thiosemicarba -zone, 6-hydroxycholest-3-methoxyoxime, 6-hydroxycholest-3-benzyl oxyoxime.Secondly, the compound pregn-4-en-3, 6, 20–trione was obtained from pregnenolone by PCC oxidation.. Then four compounds with the structure of 3- substituted pregn-4-en-6, 20-dione were synthesized through the transformation of 3-carbonyl group. They are pregn-4-en-6, 20-dioxy-3-oxime, pregn-4-en-6, 20- dioxy-3-thiosemicarbazone, pregn-4-en-6, 20-dioxy-3-methoxyoxime, pregn-4-en-6, 20-dioxy-3-benzyloxime.Finally, our research have discovered that the compounds with the choleste-ric structure in branched-chain have good anti-tumor activity and it can enhan-ce the substrate affinity to protein when the amide groups existed in steroidal molecules. According to this conclusion, using 7-deoxycholic acid as a startingmaterial, 3, 12-dione-7-deoxycholic acid was obtained by oxidation with Jones reagent. Then the N, N-dimethyl-3, 12-dioxy-7-deoxycholic amide and N-methyl-3, 12- dioxy-7 -deoxycholic amide with an amide group in side chain similar to side chain of cholesterol were synthesized by the reaction of 7-deoxycholic acid with dimethylamine or methylamine. Then through the transformation of functional groups, four new compounds were prepared. They are N, N-dimethyl -12- oxy-3-hydroximino-7-deoxycholic amide, N, N-dimethyl-12-oxy-3- thiosemicar -bazone -7-deoxycholic amide, N, N-dimethyl-12-oxy-3-methoximino- 7-deoxych -olic amide, N, N-dimethyl-12-oxy-3-benzyloximino-7-deoxycholic amide. In the meanwhile, N, N-dimethyl-3-hydroxy-12-one-7-deoxycholic amide was synthesized by selective reduction, and then through the transformation of 12-carbonyl group, a new compound N, N- dimethyl- 3- hydroxy-12-thiosemicarbazone-7- deoxycholic amide was obtained. We proposed some new synthesized methods about compounds above, and determined optimal reaction conditions. Meanwhile, scaning to compounds by the inhibition of tumor cell proliferation, it is found that benzyloximino can increase cytotoxic activity of compounds obviously. The results provide a theoretical reference for the development of new anticancer drugs, and enrich the content of steroid chemistry.