잡초과학의 새로운 과제

김대황(Kim, Dae Whang) 한국잡초학회 2011 한국잡초학회 별책(학술대회 초록집) Vol.31 No.1

Pyrimidine 유도체에 의한 완두 Acetolactate Synthase의 저해에 관한 연구

주영아,김대황,장수익,최정도,Joo, Young A,Kim, Dae Whang,Chang, Soo Ik,Choi, Jung Do 대한화학회 1997 대한화학회지 Vol.41 No.6

Acetolactate Synthase(ALS)는 가지를 가진 아미노산 valine, leucine, isoleucine의 생합성 과정에서 공통적으로 작용하는 효소이다. ALS는 서로 구조적 유사성이 없는 최근에 개발된 sulfonylurea, imidazolinone, 그리고 trizolopyrimidine계 제초제들의 공통적인 작용표적이다. 완두로부터 분리한 ALS를 이용하여 새로 합성한 4,6-dimethoxypyrimidine 유도체들의 저해활성을 측정하였다. 가장 우수한 저해활성을 나타내는 유도체는 K11570으로 $IC_{50}$값이 0.2 ${\mu}M$이다. 완두의 ALS에 대한 K11570의 저해활성은 incubation 시간이 증가함에 따라 증가하였으며, 기질 pyruvate에 대해 혼합형 저해유형을 보여주었다. K11570와 sulfonylurea Ally, 그리고 feedback 저해제 leucine에 대한 dual inhibition 실험결과 이들 저해제의 결합부위가 최소한 부분적으로 겹치는 것으로 생각된다. Arg을 변형시킨 효소는 K11570, sulfonylurea Ally, 그리고 leucine의 저해 민감도의 변화가 관찰되었으나, Trp의 변형은 저해 민감도에 영향이 없었다. Acetolactate synthase(ALS) is the common enzyme in the biosynthetic of valine, leucine, and isoleucine, and is the target of several classes of structually unrelated herbicides, including sulfonylureas, imidazolinones, and triazolopyrimidines. In an effort to develop new and desirable herbicides, we have synthesized 4,6-dimethoxypyrimidine derivatives, and examined their inhibitory activities on pea ALS. The most active compound was found to be K11570 and $IC_{50}$ value for K11570 was 0.2 ${\mu}M.$ The inhibition of pea ALS by K11570 was biphasic, showing increased inhibition with incubation time. The K11570 showed mixed-type inhibition with respect to substrate pyruvate. Dual inhibition analysis of K11570 versus sufonylurea herbicide Ally and feedback inhibitor leucine revealed that three inhibitors were competitive for binding to ALS. The arginine modified enzyme showed decreased inhibition by K11570, sufonylurea Ally, and leucine, in constrast to, tryptophan modification did not affect on the sensitivity of ALS to the inhibitors.

새로운 N-치환 benzotriazol-1-yl유도체의 항균활성에 미치는 치환기 효과

유성재,성민규,김대황,성낙도,Yu, Seong-Jae,Sung, Min-Gyu,Kim, Dae-Whang,Sung, Nack-Do 한국응용생명화학회 1997 Applied Biological Chemistry (Appl Biol Chem) Vol.43 No.1

일련의 새로이 합성된 chira핀 N-치환 benzotriazol-1-yl유도체들의 구조와 잿빛 곰광이균(Botrytis cinerea), 배 검은 무늬병균(Alternaria kikchiana) 및 고추 역병균(Phytophthora capsici) 등 3종의 곰광이균류에 대한 항균활성에 미치는 치환기의 효과를 검토한 결과, 전자끌게(${\sigma}_I$,Y>0)로써 phenoxy 또는 thiophenoxy group(X) 보다는 alkyl또는 phenyl group(Y)이 더 큰 영향을 미쳤으며 phenoxy-치환체, 1이 thiophenoxy-치환체, 2보다 높은 항균활성을 나타내었다. 항균활성에 영향을 미치는 요인으로는 소수성(${\Sigma}logP$)과 유도효과(${\sigma}_I$,Y) 및 Van der Waals(${\Sigma}Vw$) 체적(${\AA}^3$) 등 이었으며 chiral성은 활성개선에 기여하지 못하였으나 tribromomethyl-치환체, 1g는 제일 큰 활성을 나타내는 화합물이었다. Series of new chiral N-substituted benzotriazol-1-yl derivatives were synthesized and their fungicidal activities in vitro against gray mold(Botrytis cinerea), black spot(Alternaria kikuchiana) and phytophthora blight(Phytophthora capsici) were measured by the agar medium dilution method. The substituents effects between the fungicidal activities (obs. $pI_{50}$) and a various physicochemical parameters of phenoxy or thiophenoxy group(X) & alkyl or phenyl group(Y) were analyzed by the multiple regression technique. From the analyzed substituent effects, the structure-activity relationship(SAR) equations shows that the antifungal activities depend on the parameters for the optimal molecular hydrophobicity($({\Sigma}logP)_{opt}$), Van der Waals (${\Sigma}Vw$>0) volume(${\AA}^3$) and inductive constant with electron withdrawing group(${\sigma}_I$,Y>0). The activity in affected by the inductive effect (${\sigma}_I$,Y>${\sigma}_g$X) of Y-group rather than the X-group. The phenoxy substituents, 1, showed higher antifungal activity tn the thiophenoxy substituents, 2. For 1, polar substituent constant(${\sigma}^*$) was an important factor in determining the activity. And the tribromomethyl substituent, 1g showed the highest activity against the tee fungi.

인공핵산 분해효소로서 몇 가지 유기금속 화합물들의 생물활성

성낙도(Nack-Do Sung),김대황(Dae-Whang Kim),권병목(Byung-Mok Kwon),김태영(Tae-Young Kim),서일환(Il-Hwan Suh) 한국농약과학회 2000 농약과학회지 Vol.4 No.1

A series of transition metal complexes of 3,6-bis(6'-methyl-2'-pyridyl)pyridazine (L¹) and 3,6-bis(2'-pyridyl)pyridazine (L²) as artificial nuclease, 1~8 were synthesized. After determining of X-ray crystal structure, hydrolysis rate constants of phosphates, as DNA model compound and biological activities were confirmed. L²-Zn(Ⅱ) complex, 8 was shown the best hydrolysis rate constant. The L²-Ni(Ⅱ) complex, 5 and L²-Co(Ⅱ) complex, 6 showed the highest herbicidal activity against scr (Scriptus Juncoids) with excellent tolerance to rice, ORY (Oryzae sativa L.). And the L¹-Co(Ⅱ) complex, 2, L¹-Zn(Ⅱ) complex, 4 and ligand (L¹ & L²) displayed above 90% fungicidal activity against MAG (Magnaporthe grisea).

새로운 2-(4-(6-chloro-2-benzoxazolyloxy)phenoxy)-N-phenylpropionamide 유도체들의 제초활성에 관한 HQSAR 모델과 높은 활성화합물의 예측

성낙도(Nack-Do Sung),김대황(Dae-Whang Kim),정훈성(Hoon-Sung Jung) 한국농약과학회 2005 농약과학회지 Vol.9 No.4

The herbicidal activities against pre-emergence barnyard grass (Echinochloa crus-galli) by a series of new 2-(4-(6-chloro-2-benzoxazolyloxy)phenoxy)-N-phenylpropionamide derivatives as substrate molecule were studied using molecular holographic (H) quantitative structure activity relationships (HQSAR) methodology. From the based on the findings, the higher herbicidal active compounds are predicted by the derived HQSAR model. The best HQSAR model (VI-1) was derived from fragment distinction combination of atoms/bonds in fragment size, 7~10 bin. The herbicidal activities from atomic contribution maps showed that the activity will be able to increased according to the R-substituents variation of the N-phenyl ring and change of 6-chloro-2-benzoxazolyloxy group. Based on the results, the statistical results of the best HQSAR model (VI-1) exhibited the best predictability and fitness for the herbicidal activities based on the cross-validated value (q²=0.646) and non cross-validated value (r²<SUB>ncv</SUB>.=0.917), respectively. From the graphical analyses of atomic contribution maps, it was revealed that the lowest herbicidal activities depends upon the 4-(6-chloro-2-benzoxazolyloxy)phenoxy group (pred.pI??=-3.20). Particularly, the R=4-fluoro, X=isobutoxy substituent (P2) of (X)-phenoxy-N-(R)-phenylpropionamide derivative is predicted as the highest active compound (pred.pI??=9.12).

새로운 N-치환 benzotriazol-1-yl 유도체의 항균활성에 미치는 치환기 효과

성낙도,유성재,성민규,김대황 ( Nack Do Sung,Seong Jae Yu,Min Gyu Sung,Dae Whang Kim ) 한국응용생명화학회 1997 Applied Biological Chemistry (Appl Biol Chem) Vol.40 No.1

Series of new chiral N-substituted benzotriazol-1-yl derivatives were synthesized and their fungicidal activities in vitro against gray mold(Botrytis cinerea), black spot(Alternaria kikuchiana) and phytophthora blight(Phytophthora capsici) were measured by the agar medium dilution method. The substituents effects between the fungicidal activities (obs. pI_(50)) and a various physicochemical parameters of phenoxy or thiophenoxy group(X) & alkyl or phenyl group(Y) were analyzed by the multiple regression technique. From the analyzed substituent effects, the structure-activity relationship(SAR) equations shows that the antifungal activities depend on the parameters for the optimal molecular hydrophobicity((∑logP)_(opt.)), Van der Waals (∑Vw$gt;0) volume(Å^(-3)) and inductive constant with electron withdrawing group(σ_IY$gt;0). The activity in affected by the inductive effect (σ_IY$gt;σ_RX) of Y-group rather than the X-group. The phenoxy substituents, 1, showed higher antifungal activity than the thiophenoxy substituents, 2. For 1, polar substituent constant(σ^*) was an important factor in determining the activity. And the tribromomethyl substituent, 1g showed the highest activity against the three fungi.

신규제초제 개발현황

정봉진(Bong-Jin Chung),김대황(Dae-Whang Kim),조광연(Kwang-Yun Cho) 韓國雜草學會 2001 Weed&Turfgrass Science Vol.21 No.2

Phenylvinylsulfone 유도체의 제초활성

성낙도,유성재,전동주,김대황 ( Nack Do Sung,Seong Jae Yu,Dong Ju Jeon,Dae Whang Kim ) 한국응용생명화학회 1995 Applied Biological Chemistry (Appl Biol Chem) Vol.38 No.1

Post emergence herbicidal activities(pI_(50)) of X-substituted phenylvinylsulfone derivatives(S) in-vivo against rice(Oryza sativa L), Barnyard grass(Echinochloa crus-galli) and Pickerelweed(Monochoria vaginalis Presl) were measured by the pot test under paddy conditions. The (S) showed herbicidal symptom rapidly with lower activity(average pI_(50)= 2.0) as proherbicide, which was excellent tolerance to rice. The structure activity relationships(SAR) were analyzed using such a physicochemical parameters as hydrophobic(π) and molecular orbital(MO) quantity by the multiple regression technique, and discussed with quantum pharmacology. The herbicidal activities were related to the hydrophobic(π) effect of X-substituent and orbital(HOMO & LUMO) energy. In case of Pickerelweed, the effect was rationalized by parabolic function of π constant, where the optimal value of π was 1.10. An increase in hydrophobicity and negative orbital energy by the electron attracting X-substituent may contribute to the herbicidal activity. Based on results proposed from SAR analysis, the mode of herbicidal action could be assumed.

새로운 Ortho 이치환 Benzenesulfonyl Urea 유도체의 제초활성과 수용액중의 잔류성

성낙도(Nack Do Sung),김용집(Yong Jip Kim),장해성(Hae Sung Chang),김대황(Dae Whang Kim) 한국응용생명화학회 1995 Applied Biological Chemistry (Appl Biol Chem) Vol.38 No.6

The new sixteen herbicidal N-2-(1-hydroxy-2-fluoroethyl)-6-substituted(X)-benzenesulfonyl-N`-4,6-dimethoxypyrimidinyl-2-yl urea derivatives(S) were synthesized and thier herbicidal activities(pI_(50)) in vivo against rice(Orysa Sativa L.), Barnyard grass(Echninochloa orizicola) and Bulrush(Scirpus juncoides) were measured by the pot test under paddy conditions. The structure activity relationship(SAR) were studied using the physicochemical parameters of ortho-substituents(X) and hydrolysis rate constant(logk) and herbicidal activities by the multiple regression technique. The SAR suggested that the herbicidal activities were more dependant on the hydrolysis rate constant(logk$gt;0) than the steric constants (Es$lt;L1(or B₄)$lt;0), small width(B₄) and length(L₁). Among them, halogens(2 & 5), methyl(15) and non(H) substituent(1) showed higher herbicidal activity for weeds which was not tolerent to rise and weeds. The herbicidal activity was increased and the persistency in aqueous solution was decreased by electron donating(σ0$lt;0) groups as ortho-substituent(X). From the relationship equation between herbicidal activity and hydrolysis rate constant, it was assumed that the both reactions would be proceeds with similar process. And the conditions on the ortho substituents to show higher herbicidal activity and the persistency in aqueous solution were also discussed.

신규 Sulfonylurea 제초제의 합성과 제초 특성

류재욱(Jae Wook Ryu),김병철(Byung Chul Kim),정근회(Kun Hoe Chung),장해성(Hae Sung Chang),고영관(Young Kwan Ko),우재춘(Jae Chun Woo),구동완(Dong Wan Koo),김대황(Dae-Whang Kim) 한국농약과학회 2002 농약과학회지 Vol.6 No.4

New and fast degradable sulfonylurea derivaties possessing N-methylureido group were synthesized and their herbicidal effects were tested under the upland in greenhouse. N-methylureido benzenesulfonylureas showed better herbicidal activity against grass weeds than broad leaf weeds under post emergence.