Synthesis And Evaluation Of The Structure-Immunosuppressive Activity Relationships Of Pseudolaric Acids B Derivatives

Objective Immunization drugs are developed in the 1970s,which is a new class of therapeutic agents.Immunosuppressants can uppress the body’s immune response,and inhibit proliferation and function of T cells and B cells.Immunosuppressant is used for organ transplantation and autoimmune diseases,such as rheumatoid arthritis,erythematosus,dermatomycoses,membranous glomerulonephritis,inflammatory bowel disease,autoimmune hemolytic anemia and so on.Pseudolarix,the root bark of Pseudolarix kaempferi Gord,was always used as traditional Chinese medicine to treat tinea disease.Pseudolaric acid B is a new diterpene acid compound,which is extract from pseudolarix.The basic structure of pseudolaric acid B is a special azulenesmoiety,which both has lactone ring structure and conjugated diene acid side chain.The structure is scarce in natural products,so pseudolaric acid B may be an ideal lead compounds as immunosuppressive drugs.Modern pharmacological experiments have shown that pseudolaric acid B has many pharmacological activities,such as antifungal,anti-fertility inducing the apoptosis of tumorcells,and anti-angiogenesis activity.Pseudolaric acid B with immunosuppressive activity were found by our group recently.In order to find potential immunosuppressive agents with high efficacy and low toxicity,a series of novel pseudolaric acid B derivatives were synthesized and evaluated on their immunosuppressive activities.The structural transformation of pseudolaric acid B is ongoing in our laboratory to identify structure activity relationship.Content Under the guidance of medication mixing principle and ibin sharansky five principles,we made further study on structure activity relationship of pseudolaric acid B,which amied at C-4 and C-18.In addition,from the perspective of the total synthesis,the synthesis of pseudolaric acid B is difficult.From the perspective of biological sources,pseudolaric acid B is extract from pseudolarix,which is two national protected plants.Mentioned above,we found that indole also has certain immunosuppressive activity,so a series of indole derivatives were synthesized.The structures of these compounds in this article were confrmed by spectropic analysis of HR-ESI-MS,1H-NMR and 13C-NMR.The inhibitory activity on ConA-induced murine T and LPS-induced murine B cell proliferation of all the synthesized compounds was tested with mycophenolatemofetil(MMF)as the control.Others,we valuated the cytotoxicity of these compoundson murine spleen cells with MTT assay.Methods 1.Heterocyclic aromatic ring and aliphatic amines were introduced at C-18 by acylation of condensation,so a series of amides compounds of pseudolaric acid B were synthesized.2.C-18 was reduced and benzene ring,furan ring,pyridine ring carboxylic acid were introduced at C-18 by acylation of condensation,so a series of esterscompounds of pseudolaric acid B were synthesized.3.C-4 without acetyl,18-COOH of pseudolaric acid B was transformed to methylene series.4.A series of indole derivatives were synthesized by N-alkylation reaction,acylation of condensation,knoevenagel Reaction,wittig Reaction,Vilsmeier-Haack Reaction,williamson and so on.5.Preparation of mouse lymphocyte suspension,the inhibitory activity on murine T and murine B cell proliferation and cytotoxicity of all the synthesized compounds was tested with mycophenolatemofetil(MMF)as the control by MTT assay.Results Four series and forty-eight pseudolaric acids B derivates were synthesized.The first series,eight amides derivatives of pseudolaric acid B.The second series,seventeen C-18 alcoholic hydroxylesters derivatives of pseudolaric acid B.The third series,five C-4 without acetyl,18-methylene of pseudolaric acid B.The fourth series,eighteen indole derivatives.The structures of these compounds were confrmed by spectropic analysis of HR-ESI-MS,1H-NMR and 13C-NMR.The immunosuppressive activity of all the synthesized compounds was tested by MTT assay in vitro.Conclusion 1.When aromatic heterocyclic was introduced at C-18,it is beneficial for inhibition of T lymphocyte proliferation.It made no diffidence,when heterocyclic and saturated aliphatic ring was introduced at C-18 simply.2.C-18 alcoholic hydroxyl esters compounds of pseudolaric acid B have many advantages such as high activity and low toxicity in vitro.3.The amides compounds C-4 without acetyl,18-COOH of pseudolaric acid B have better immunosuppressive activity than PB,which showed that C-4 acetyl is not the essentialgroups.4.The most of indole derivatives have no immunosuppressive activity.The cytotoxic activity had not obviously connetion with the anti-proliferation activity.