Metallocenes against Parasites

  • Author:
  • Published: 07 October 2016
  • Copyright: Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
  • Source / Publisher: Dalton Transactions/Royal Society of Chemistry (RSC)
  • Associated Societies: Royal Society of Chemistry (RSC), UK
thumbnail image: Metallocenes against Parasites

Parasitic nematodes, such as hookworms or heartworms, can cause diseases in both plants and animals. Drugs against such parasites are called antihelminthics. Their use is widespread, e.g., in pets, and as a result, some of the parasites have developed resistances against them. New antiparasitic drugs can overcome this temporarily, but the race against resistances is ongoing.

Robin B. Gasser, University of Melbourne, Parkville, Australia, Gilles Gasser, Université Pierre et Marie Curie, Paris, France, and colleagues have modified the drug monepantel, a member of a relatively new class of antiparasitics, to overcome these emerging resistances. Monepantel consists of an aryloxy group, a chiral spacer, and a benzamide unit. The team modified the compound by substituting the groups at either end of the molecule with metallocene groups (ferrocene or ruthenocene).

To prepare the ferrocene derivatives, the researchers reacted 2-amino-2-hydroxymethylproprionitrile with activated ferrocencarboxylic acid. The resulting intermediate was converted into a ferrocenyl-substituted monepantel analogue using a Williamson ether synthesis in the presence of NaH and 3-fluoro-4-(trifluoromethyl)benzonitrile. The team also prepared disubsituted analogues with two ferrocenyl groups, as well as ruthenocenyl analogues which are structurally identical to the ferrocenyl compounds.

The biological activity of the compounds was tested on the parasitic nematodes Haemonchus contortus (barber's pole worm) and Trichostrongylus colubriformis. The ruthenocyl compounds were not active, but two of the ferrocenyl derivatives showed nematocidal activity. According to the team, the synthesized compounds could serve as leads for the development of new classes of anti-parasitic agents.


Article Views: 1523

Sign in Area

Please sign in below

Additional Sign In options

Please note that to comment on an article you must be registered and logged in.
Registration is for free, you may already be registered to receive, e.g., the newsletter. When you register on this website, please ensure you view our terms and conditions. All comments are subject to moderation.

Article Comments - To add a comment please sign in

If you would like to reuse any content, in print or online, from, please contact us first for permission. more

Follow on Facebook Follow on Twitter Follow on YouTube Follow on LinkedIn Follow on Instagram RSS Sign up for newsletters

Magazine of Chemistry Europe (16 European Chemical Societies) published by Wiley-VCH