Antiparasitic activities of new lawsone Mannich bases

• Published in: Archiv der Pharmazie (Weinheim) Vol. 352; no. 11; pp. e1900128 - n/a
• Main Authors: Al Nasr, Ibrahim, Jentzsch, Jana, Winter, Isabel, Schobert, Rainer, Ersfeld, Klaus, Koko, Waleed S., Mujawah, Adil A. H., Khan, Tariq A., Biersack, Bernhard
• Format: Journal Article
• Language: English
• Published: WEINHEIM Wiley 01.11.2019; Wiley Subscription Services, Inc
• Subjects: Antiparasitic Agents - chemical synthesis; Antiparasitic Agents - chemistry; Antiparasitic Agents - pharmacology; antiparasitic drugs; Chemistry; Chemistry, Medicinal; Chemistry, Multidisciplinary; Dose-Response Relationship, Drug; lawsone; Leishmania major - drug effects; Life Sciences & Biomedicine; Mannich base; Mannich Bases - chemical synthesis; Mannich Bases - chemistry; Mannich Bases - pharmacology; Molecular Structure; Naphthoquinones - chemical synthesis; Naphthoquinones - chemistry; Naphthoquinones - pharmacology; neglected tropical diseases; Parasitic Sensitivity Tests; Pharmacology & Pharmacy; Physical Sciences; Protozoa; salicyl derivatives; Science & Technology; Structure-Activity Relationship; Toxoplasma - drug effects; Trypanosoma brucei brucei - drug effects; salicyl derivatives; neglected tropical diseases; ASSAY; ANTICANCER ACTIVITIES; antiparasitic drugs; MILTEFOSINE; PROLIFERATION; lawsone; Mannich base; DERIVATIVES
• ISSN: 0365-6233; 1521-4184
• DOI: 10.1002/ardp.201900128

A series of new lawsone Mannich bases derived from salicylaldehydes or nitrofurfural were prepared and tested for their activities against Leishmania major, Toxoplasma gondii, and Trypanosoma brucei brucei parasites. The hydrochloride salts 5a and 6a of the Mannich bases 2a and 3a, derived from unsubstituted salicylaldehyde and long‐chained alkyl amines, were selectively and strongly active against T. gondii cells and appear to be new promising drug candidates against this parasite. Compound 6a showed an even higher activity against T. gondii than the known lawsone Mannich base 1b. Compound 4a, derived from salicylaldehyde and 2‐methylaminopyridine, was also distinctly active against T. gondii cells. The derivatives 3a (salicyl derivative), 3b (3,5‐dichloro‐2‐hydroxyphenyl derivative), and 3d (5‐nitrofuranyl derivative) as well as the hydrochlorides 6a and 6b were also efficacious against T. b. brucei cells with compounds 3a and 3b being more selective for T. b. brucei over Vero cells when compared with the known control compound 1b. The derivatives 5a, 5c, 6a, and 6c proved to be up to five times more active than 1b against L. major promastigotes and up to four times more efficacious against L. major amastigotes. New lawsone Mannich bases derived from salicylic aldehydes and long‐chained primary alkyl amines were prepared by simple methods. Some promising derivatives were distinctly more active against and selective for Toxoplasma gondii and Leishmania major cells than a known antiparasitic lawsone Mannich base.