1. Synthesis directed towards antimicrobial purines Lise-Lotte Gundersen Department of Chemistry, University of Oslo, Norway

2. Nature 2004, 430, 242 >25% of all deaths worldwide direct result from infection

3. History of antimicrobial drugs Quinine (Cinchona pubescens; malaria) ca. 1825 Salvarsan (syphilis) 1912 Sulfa drugs (bacterial infections) ca. 1935

4. 1928: Penicillum notatum (= P. chrysogenum) inhib. Staph. aureus growth (Flemming) 1938: Isolation “penicillin” (Florey, Chain) 1941: Penicillin on humans 1943: Big-scale production penicillin 1943: Structure penicillin G proposed (Chain) 1945: Nobelprize in medicine; Fleming, Chain, Florey 1945: X-ray structure penicillin G (Hodgkin) 1957: Synthesis penicillin G (Sheehan) Penicillin

5. 1944: Streptomycine (aminoglykoside) 1945:Cefalosporine C (cefalosporines) 1947: Chloramphenikol 1948: Chlorotetraycline (tetracyclines) 1950: Picromycine (makrolides) 1959:Rifamycine (ansamycines) US Surgeon General, 1967: “The war against infectious diseases has been won” Bacitracine (peptides) Other classes of antibacterial antibiotics

6. Nature 2004, 430, 242 Emerging and re-emerging infections ca. 1980 (AIDS)-date.

7. Nature 2004, 430, 242 Nature 2004, 431, 892: “Antibiotics are the worst sort of pharmaceuticals because they cure the disease”

8. AgelasinesAgelasiminesAsmarines Our Activities: Purine-Containing Antimicrobial Natural Products from Marine Sponges Selective Antimycobacterial Purines

9. Marine Sponges?

10. Agelasines Isolated from marine sponges (Agelas sp.) 11 comp. (Agelasine A - I, epiagelasine C and ageline B) known to date Total syntheses other groups: Agelasine A, B and C, and (±) agelasine F Bioactivities: Cytotoxic Antimicrobial Inhibition of Na,K-ATPase Brown Tube Sponge: Agelas sp. 2.5 feet long

11. Synthesis of Trixagol and Agelasine E Isolated from Bellardia trixago TL, 1978, 3491 Isolated from Agelas sp. Tetrahedron Lett. 1984, 2989

12. Synthesis of Trixagol and ent-Trixagol Bakkestuen et al., Tetrahedron 2003, 59, 115 Trixagol

13. Synthesis of Agelasine E and ent-Agelasine E Bakkestuen et al., Org. Biomol. Chem. 2005, 3, 1025

14. Synthesis of Agelasine D Agelasine D Manool Sclareol Salvia sclarea (Clary Sage) Isolated from Agelas sp. Tetrahedron Lett. 1984, 2989

15. Synthesis of Agelasine D - Initial Approach Drawbacks: Lack of selectivity Utenova et al., Tetrahedron Lett. 2004, 45, 4233

16. Improved Synthesis of Agelasine D Synthesis of geometrically pure allyl bromide Vik et al., J. Nat. Prod. 2006, 69, 381

17. Improved Synthesis of Agelasine D - Regioselective N-alkylation Vik et al., J. Nat. Prod. 2006, 69, 381

18. Synthesis directed towards Agelasine F Isolated from Agelas sp. Tetrahedron Lett. 1984, 2989 Isolated from pennyroyal (Mentha Pulegium)

19. Proszenyak et al., Unpublished

21. Intermediate in synthesis of other natural products ?

22. Synthetic intermediate - simpler side chain, Even better activities than naturally occuring agelasines!! Type A structureType B structure Structure - Activity Relationships Type A more active than type B structure ( otherwise same subst.) R’ must be relatively long and preferably contain unsaturation(s)

23. Antimicrobial activities Vik et al., Bioorg. Med. Chem. 2007, 15, 4016 Also activity against several cancer cell lines

24. Tuberculosis (TB) Agelas dispar WHO (1993): TB a “global emergency” AIDS Resistant strains Migration Powerty Ca 3 mill deaths / year Bacterial infection (Mycobacterium tuberculosis) Inhalation Lung most commonly attacked All organs, incl. CNS, may be attacked Before 1950; 50% of all sick died First effective drug: Streptomycin (1943) - Toxic Several less toxic drugs developed ca 1950-1962

25. Vik et al., Bioorg. Med. Chem. 2007, 15, 4016 Planta Med. 2007, 73, 1410

26. Activity Patogenic Protozoa Tropical diseases chloroquine 0.04  g/mL miltefosine 0.24  g/mL benznidazole 0.25  g/mL melarsoprol 0.005  g/mL Vik et al., Unpublished

27. Viceral Leichmaniasis / Kala azar / Black Fewer Infection - Leichmania donovani s.l. (protozoa) Transmitted by sandflies Deathly if untreated; 59.000 deaths/year Treatment: Long time with antimon-compounds (miltefosine, amfotericin B) > 90% i Bangladesh, Brasil, India, Sudan Chagas disease / American Sleeping Sickness Infection - Trypanosoma cruzi (protozoa) Transmitted by insects (Teger) Deathly if not treated in time (Ofthen long period without symptoms); 13.000 deaths/year Treatment: Nifurtimox or benznidazol, in the early phase South- & Central America

28. AgelasinesAgelasiminesAsmarines Our Activities: Purine-Containing Marine Natural Products from Marine Sponges Compounds with Antimicrobial Activities

29. Asmarines Isolated from marine sponges (Raspailia sp.) 11 comp. (Asmarine A - J) No total syntheses Bioctivities: Cytotox.

30. Previous strategies for construction of the 7-membered ring No ex. of formation of bond c or d

31. Formation of bond d - Initial attempts Vik et al. Tetrahedron. Lett. 2007, 48, 1931 Ring Closing Metathesis (RCM)

32. Vik et al. Tetrahedron. Lett. 2007, 48, 1931

33. AgelasinesAgelasiminesAsmarines Our Activities: Purine-Containing Antimicrobial Natural Products from Marine Sponges Selective Antimycobacterial Purines

34. MIC M. Tub. 0.78  g/mL Rifampin: MIC M. Tub. 0.25  g/mL Langli et al., Tetrahedron 1996, 52, 5625 Bakkestuen et al. Bioorg. Med. Chem. Lett. 2000, 10, 1207 Gundersen et al. J. Med. Chem. 2002, 45, 1381

35. Antimycobacterial 6-(2-Furyl)purines: The N-9 Substituents Gundersen et al. J. Med. Chem. 2002, 45, 1381 Bakkestuen et al., Tetrahedron Lett., 2003, 44, 3359

36. Summary SAR knowledge Gundersen et al. J. Med. Chem. 2002, 45, 1381 Bakkestuen et al. J. Med. Chem. 2005, 48, 2710 Brændvang et al. Bioorg. Med. Chem. 2005, 13, 6360 Brændvang et al. Bioorg. Med. Chem. 2007, 15, 7144 but also non-purine analogs...

37. Acknowledgements Synthesis Dr. Anne Kristin Bakkestuen Dr. Morten Brændvang Abhijit K. Datta Veronika Ernst Anthony James Aisvareya Kulendern Dr. Geir Langli Dr. Pedro O. Miranda Dr. Edyta Nagrodzka Dr. Agnes Prozenyak Matthew L. Read Heidi Roggen Linda W. Tangen Dr. Bibigul T. Utenova Dr. Anders Vik Bioactivities Prof. Lars Bohlin & co-workers Dr. Colin Charnock Tuberculosis Antimicrobial Acquisition and Coordinating Facility (TAACF) WHO - TDR Financial Support NFR (FRINAT & KOSK) UiO