ABSTRACT
Objective:To study the acute toxicity in mice and cytotoxicity of the impuritiy(3-amino-2-piperidinone hydrochloride) in ornithine. Methods:The mice were given the impurity by intravenous injection.The acute toxicity was observed and LD50in mice was calculated by Bliss method. According to the result of LD50,the mice were given the impurity respectively at high,medium and low dose. The changes of general condition and body weight were recorded,and the blood biochemical indices and histomorphology of organs and tissues were observed after 14 days. The cytotoxicity was measured on fibroblasts(L929) cells. Results:The LD50and 95% con-fidence limit of the impurity (intragastric administration) was 758.49-848.08 mg·kg-1.All the detected indices of the three groups (660,330 and 170 mg·kg-1) including general condition,weight change,biochemical indices,organ morphological and histological change were all within the normal ranges. The impurity significantly decreased the viability of L929 cells. The NOAEL value was 660 mg·kg-1in mice. Conclusion:The impurity has certain toxicity to mice and cells. The data can provide experimental basis for the quality standard establishment for ornithine and the safety improvement in clinic use.
ABSTRACT
An improved and practical synthesis of racemic 11-demethylcalanolide A [(±)-1] was developed. This improved process involved Pechmann reaction on phloroglucinol with ethyl butyrylacetate to give 5, 7,-dihydroxy-4-n-propylcoumarin(3). Poly phosphoric acid (PPA) catalyzed acylation of compound(3) with crotonic acid, then intramolecular cyclization was achieved simultaneously in one step to afford the key intermediate chromanone(4). A microwave assisted synthetic method preparing chromene(6) using chromenynation of chromanone(4) with 1, 1-diethoxy-methyl-2-butene was conducted. Luche reduction of chromene(6) using NaBH<,4> with CeCl3·7H2O preferably gave (±)-1. The overall yield of this four step synthesis of (±)-1 was around 32% increasing one fold more than that of the previous method. An in vitro investigation showed that (±)-1 exhibited inhibitory activities against both wild-type and drug-resistant HIV-1 in HIV-1 RT and cell culture assay, and significant synergistic effects in combination with AZT, T-20, and indinavir. Its LD50 of acute toxicity in mice by intragastric administration and by intraperitoneal injection were 735.65mg·kg-1 and 525.10mg·kg-1, respectively. The C<,max> and AUC<,0-∞> were 0.54μg·mL-1 and 1.08(μg·mL-1)·h, respectively. The dynamics study of the inhibition of mice sera on HIV-1 RT showed that mice treated with 100mg·kg-1 (±)-1 once intraperitoneally were similar to that of 5mg·kg-1 of known clinical effective anti-HIV-1 drug neverapine. The results suggested that further investigation of the anti-HIV candidate (±)-1 was warranted.