Synthesis Of Phenylthiourea Compounds And Their Effects On Zebrafish

The thiourea-derived compound contains a structure of-NH-CS-NH-,and having a thiocarbonyl group(=C=S),is widely used in the fields of chemistry,industry,agriculture,medicine,and so on.Such compounds have many application,for example,as important chemical intermediates,anti-corrosion,plant herbicides and growth regulators,anti-tumor,anti-virus,sterilization,etc.1-phenyl-2-thiourea(PTU),a commonly used inhibitor of melanin,is a sulfur-containing tyrosinase inhibitor.It has stronger melanin inhibiting activity than other common used compounds(arbutin,kojic acid).However,this compound is mainly used in the melanin research of zebrafish,and there is no report about inhibiting melanin in whitening cosmetics products because of its high toxicity.There is few studies on different substituents on benzene ring of N-phenylthiourea.In this dissertation several N-phenylthioureas compounds was synthesized,and screen for less toxicity and higher activity to inhibit melanin.Seven phenyl thiourea compounds were synthesized by a simple and easy method.The corresponding substituents of the aniline derivative,hydrochloric acid(HCl)and potassium thiocyanate(KSCN)were mainly used as a starting material,target products are obtained by a salt formation and a thiourea reaction.The synthesized compounds were characterized by silica gel thin layer chromatography(TLC),melting point detection,infrared spectroscopy(IR)and ~1H NRM.a:3,5-dimethylphenylthiourea,b:2,5-dimethylphenylthiourea,c:3,4-dimethylphenyl thiourea,d:3-chloro-4-methylphenylthiourea,e:3,4-dichlorophenylthiourea,f:2,5-dichlorophenylthiourea,j:o-chlorophenylthiourea.The above compounds were tested for biological activity,N-phenylthiourea was selected as the positive control,and the wild AB strain zebrafish was used as the model.When the hatching was 23 h,the culture solution was replaced with the culture solution with each compounds.At 72 hpf,the hatching,survival and teratogenic effects were counted.The OD value was calculated by stereomicroscope observation,microplate reader measurement and image software.In seven synthesized phenyl thiourea compounds,two of them,compounds c and d,had the greatest effect on melanin in zebrafish and inhibited melanin more strongly than the positive control.From the results of stereomicroscope,microplate reader and image software,the best concentration of compound a、b、c、d、e、f、j on zebrafish melanin inhibition was 0.075mmol/L、0.075 mmol/L、0.04 mmol/L、0.04 mmol/L、0.05 mmol/L、0.05 mmol/L、0.05mmol/L,respectively;N-phenylthiourea as the positive control,on zebrafish melanin inhibition is preferably at 0.075 mmol/L.Among them,compound e has a great influence on the development of zebrafish at≥0.075 mmol/L,which would lead to certain teratogenic effects.When compound f was at≥0.05 mmol/L,it would affect the developmental morphology and mortality of zebrafish;compound j exhibits different degrees of teratogenicity at≥0.075 mmol/L.In the OD value measured by the microplate reader,the activity of the compound c was found>compound d>positive control group,and the activity of the compound c was found in the heartbeat experiment>positive control group>compound d.