Varacin

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Varacin
Varacin skeletal structure Varacin structure.svg
Varacin skeletal structure
Varacin 3D ball.png
Names
Preferred IUPAC name
2-(8,9-Dimethoxy-1,2,3,4,5-benzopentathiepin-6-yl)ethan-1-amine
Identifiers
3D model (JSmol)
ChEMBL
ChemSpider
PubChem CID
  • InChI=1S/C10H13NO2S5/c1-12-7-5-6(3-4-11)9-10(8(7)13-2)15-17-18-16-14-9/h5H,3-4,11H2,1-2H3 X mark.svgN
    Key: HIKCOAGMCNIBMP-UHFFFAOYSA-N X mark.svgN
  • InChI=1/C10H13NO2S5/c1-12-7-5-6(3-4-11)9-10(8(7)13-2)15-17-18-16-14-9/h5H,3-4,11H2,1-2H3
    Key: HIKCOAGMCNIBMP-UHFFFAOYAP
  • NCCc2cc(OC)c(OC)c1SSSSSc12
Properties
C10H13NO2S5
Molar mass 339.540 g/mol
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
X mark.svgN  verify  (what is  Yes check.svgYX mark.svgN ?)

Varacin is a bicyclic organosulfur compound originally found in marine Ascidiacea from the Polycitor genus. [1] It contains an unusual pentathiepin ring which reacts with DNA, and varacin and synthetic analogues have been investigated for their antimicrobial and antitumour properties. [2] [3] Because of its potent biological activity and unusual and challenging ring system, it has been a popular target of efforts toward its total synthesis. [4] [5] [6]

By virtue of the unsymmetrically substituted benzopentathiepin ring system, varacin and a few related polysulfane natural products exist as potentially isolable enantiomers as a result of planar chirality. [7]

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References

  1. Makarieva TN, Stonik VA, Dmitrenok AS, Grebnev BB, Isakov VV, Rebachyk NM, Rashkes YW (February 1995). "Varacin and three new marine antimicrobial polysulfides from the far-eastern ascidian Polycitor sp". Journal of Natural Products. 58 (2): 254–8. doi:10.1021/np50116a015. PMID   7769392.
  2. Greer A (October 2001). "On the origin of cytotoxicity of the natural product varacin. A novel example of a pentathiepin reaction that provides evidence for a triatomic sulfur intermediate". Journal of the American Chemical Society. 123 (42): 10379–86. doi:10.1021/ja016495p. PMID   11603989.
  3. Brzostowska EM, Greer A (January 2003). "The role of amine in the mechanism of pentathiepin (polysulfur) antitumor agents". Journal of the American Chemical Society. 125 (2): 396–404. doi:10.1021/ja027416s. PMID   12517151.
  4. Behar V, Danishefsky SJ (1993-07-01). "Total synthesis of the novel benzopentathiepin varacinium trifluoroacetate: the viability of "varacin-free base"". Journal of the American Chemical Society. 115 (15): 7017–7018. doi:10.1021/ja00068a087. ISSN   0002-7863.
  5. Ford PW, Narbut MR, Belli J, Davidson BS (1994-10-01). "Synthesis and Structural Properties of the Benzopentathiepins Varacin and Isolissoclinotoxin A". The Journal of Organic Chemistry. 59 (20): 5955–5960. doi:10.1021/jo00099a026. ISSN   0022-3263.
  6. Toste FD, Still IW (1995-07-01). "A New Route to the Synthesis of the Naturally Occurring Benzopentathiepin Varacin". Journal of the American Chemical Society. 117 (27): 7261–7262. doi:10.1021/ja00132a033.
  7. Brzostowska, Edyta M.; Paulynice, Martine; Bentley, Ronald; Greer, Alexander (2007-07-01). "Planar Chirality due to a Polysulfur Ring in Natural Pentathiepin Cytotoxins. Implications of Planar Chirality for Enantiospecific Biosynthesis and Toxicity". Chemical Research in Toxicology. 20 (7): 1046–1052. doi:10.1021/tx7000465. ISSN   0893-228X.