In the experiments using intranasal (i/n)
infection of mice with the ectromelia virus (EV) in a dose 10 LD50/head (10
x 50% lethal doselhead) or with the monkaypox virus (MPXV) in a dose 10 ID50/head (10
x 50% infective dose/ head) it was demonstrated that the
antiviral efficiency of chemical compounds - the condensed derivatives of pyrrolidin-2,5-dion, as well as their predecessors and the nearest analogues, synthesized in Novosibirsk Institute of Organic Chemistry of the Siberian Branch of the Russian Academy of Sciences (NIOCH SB RAS) was observed. As a positive control we used the antipoxvirus chemical preparation
ST-246 available from
SIGA Technologies Inc. (USA), synthesized in NIOCH SB RAS by the technique suggested by the authors. It was demonstrated that the compound
NIOCH-14 (7-[N'-(4-Trifluoromethylbenzoil)-hydrazidecarbonil]-tricyclo[3.2.2.02,4]non-8-en-6-
carbonic acid) possessed comparable with
ST-246 antiviral activity concerning EV and MPXV on all indicators used. Therefore, at
infection of mice with EV (strain K-1) and peroral administration of
NIOCH-14 and
ST-246 in a dose 50 mkg/g of mouse weight (12-14 g) within 10 days the survival rate and average life expectancy of mice authentically exceeded the control levels. EV titers in lungs through 6 days after
infection in the same groups were lower than in the control. In addition to that, after 7 days of
infection of mice with MPXV (strain V79-1-005) and daily peroral administration of
NIOCH-14 and
ST-246 in a dose 60 mkg/g of mouse weight (9-11 g) authentic decrease in a part of infected animals and MPXV titers in lungs was observed.