Phenyl substituent effect on the fungicidal activity of N-Phenyl-O-phenylthionocarbamate derivatives

N-Phenyl-O-phenylthionocarbamate 유도체의 항균활성에 미치는 phenyl 치환기의 효과

A series of N-phenyl-O-phenylthionocarbamate derivatives were synthesized and determinated fungicidal activities in vitro against gray mold (Botrytis cinerea) and capsicum phytophthora blight (Phytophthora capsici) which showed resistance and sensitivity to benomyl and metalaxyl as systemic fungicides, respectively. The structure-activity relationship (SAR) was investigated by Free-Wilson analysis method and Hansch method. From the basis on the findings, the N-phenyl(X) groups had more contributions than O-phenyl(Y) groups did and ortho-substituents on the N-phenyl group showed high fungicidal activities. Especially, 4-cyano substituent, 2 as X-group showed 50% inhibition($pI_{50}=5.50$) of hyphae growth at 0.8ppm against resistance P. capsici (RPC) And hydroxyl substituents, 12 and 23 displayed the highest fungicidal activity against resistant B. cinerea (RBC), sensitive B. cinerea (SBC), and sensitive P. capsici (SPC). Antifungal activities of SPC were dependent upon molar refractivity (MR) constant and those of others relied on hydrophobic parameters (${\sigma}$ and logP). For increasing fungicidal activity against RPC and SBC, the optimum values of the sigma (${\sigma}$) and field(F) constants as electron withdrawing groups were 0.32 and 0.18, respectively.

일련의 N-phenyl-O-phenylthionocarbamate 유도체을 합성하고, benomyl 및 metalaxyl 등 2종의 침투성 살균제에 대하여 저항성과 감수성을 나타내는 잿빛곰팡이병균(Botrytis cinerea) 및 고추 역병균(Phytophthora capsici)에 대한 항균활성(obs. $pI_{50}$)과 치환기 변화에 따른 구조-활성관계(SAR)를 Free-Wilson방법과 Hansch방법으로 검토하였다. 치환기의 기여도는 O-phenyl group (Y)보다 N-phenyl group(X)이 비교적 높았으며 ortho-치환체(X)들이 다른 치환체들에 비해 양호한 항균활성을 나타내었다. 특히 X-치환기로써 4-cyano 치환체, 2는 0.8ppm에서 저항성 고추역병균(RPC)에 대한 균사생장을 50%저해($pI_{50}=5.50$)하였으며 hydroxyl 치환체, 12와 23는 저항성 및 감수성 잿빛 곰팡이균(RBC, SBC)과 감수성 고추역병균(SPC)에 대하여 대체로 높은 항균활성을 나타내었다. SPC균은 MR상수에 의존적인 항균활성을 나타내었고 나머지 3종의 균에 대한 항균활성은 공통적으로 소수성(${\pi}$ 및 logP)에 의존적이었다. 그리고 RPC 및 SBC균의 항균활성을 향상시키기 위한 조건으로는 전자끌게로써 적정값의 ${\sigma}$상수(${\sigma}_{opt.}=0.32$) 및 F상수($F_{opt.}=0.181$)를 갖는 치환기가 치환되어야 항균활성이 개선될 것으로 예상되었다.