New herbicidal derivatives of 1,2,4‐triazolo [1,5‐a] pyrimidine

Kleschick, William A.; Costales, Mark J.; Dunbar, Joseph E.; Meikle, R. W.; Monte, William T.; Pearson, Norman R.; Snider, Sigrid W.; Vinogradoff, A. P.

doi:10.1002/ps.2780290309

Cited by 84 publications

(53 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Included were cerealtolerant (chlorsulfuron, metsulfuron methyl, thifensulfuron methyl, triasulfuron), soybean-tolerant (chlorimuron ethyl), and nonselective (sulfometuron methyl) sulfonylurea herbicides. In addition, a different chemical class of ALS inhibitor as represented by 2,6-dichlorosulfonanilide (18) (Fig. 2) was [PYRUVATE], mM Figure 6.…”

Section: Resultsmentioning

confidence: 99%

“…The mode of action of the sulfonylurea (5,20,26) as well as the imidazolinone (30) and sulfonanilide (18) herbicides is the inhibition of ALS (see abbreviation list in Table I) (also known as acetohydroxyacid synthase, EC 4.1.3.18), the first enzyme common to the biosynthesis of the branched-chain amino acids, Leu, Ile, and Val. Chlorsulfuron, a sulfonylurea herbicide used in cereals, is wheat (Triticum aestivum L.)-tolerant because the crop metabolizes the chlorsulfuron to nonphytotoxic products more quickly than susceptible weeds (32).…”

mentioning

confidence: 99%

See 1 more Smart Citation

Mechanism of Sulfonylurea Herbicide Resistance in the Broadleaf Weed, Kochia scoparia

Cotterman²,

1990

View full text Add to dashboard Cite

Selection of kochia (Kochia scoparia) biotypes resistant to the sulfonylurea herbicide chlorsulfuron has occurred through the continued use of this herbicide in monoculture cereal-growing areas in the United States. The apparent sulfonylurea resistance observed in kochia was confirmed in greenhouse tests. Fresh and dry weight accumulation in the resistant kochia was 2-to >350-fold higher in the presence of four sulfonylurea herbicides as compared to the susceptible biotype. Acetolactate synthase (ALS) activity isolated from sulfonylurea-resistant kochia was less sensitive to inhibition by three classes of ALS-inhibiting herbicides, sulfonylureas, imidazolinones, and sulfonanilides. The decrease in ALS sensitivity to inhibition (as measured by the ratio of resistant 150 to susceptible 150) was 5-to 28-fold, 2-to 6-fold, and 20-fold for sulfonylurea herbicides, imidazolinone herbicides, and a sulfonanilide herbicide, respectively. No differences were observed in the ALS-specific activities or the rates of ["4C]chlorsulfuron uptake, translocation, and metabolism between susceptible and resistant kochia biotypes. The Km values for pyruvate using ALS from susceptible and resistant kochia were 2.13 and 1.74 mm, respectively. Based on these results, the mechanism of sulfonylurea resistance in this kochia biotype is due solely to a less sulfonylurea-sensitive ALS enzyme.The loss of effective control by pesticides of weeds, insects, and fungi because of resistance is a well known, established phenomenon (9). Among weeds, triazine resistance was first reported in 1970 (27). Subsequently, resistance to several other herbicides in addition to the triazines has occurred in weeds (2, 10). The continued use of a single control agent is often a common feature in cases of resistance.The sulfonylureas are highly active herbicides that have been in commercial use since 1982. The mode of action of the sulfonylurea (5,20,26) as well as the imidazolinone (30) and sulfonanilide (18) herbicides is the inhibition of ALS (see abbreviation list in Table I) (also known as acetohydroxyacid synthase, EC 4.1.3.18), the first enzyme common to the biosynthesis of the branched-chain amino acids, Leu, Ile, and Val. Chlorsulfuron, a sulfonylurea herbicide used in cereals, is wheat (Triticum aestivum L.)-tolerant because the crop metabolizes the chlorsulfuron to nonphytotoxic products more quickly than susceptible weeds (32). This differential selectivity based on metabolism is contrasted by selectivity due to differences in target site sensitivity as obtained by selection or production of sulfonylurea-resistant bacteria (20,34), yeast (7) (25) and prickly lettuce (Lactuca serriola L.) (22) in certain cereal-growing areas. In this paper, the mechanism by which kochia is resistant to the sulfonylurea and imidazolinone herbicides is described. MATERIALS AND METHODS Whole Plant Experiments

show abstract

Section: Resultsmentioning

confidence: 99%

mentioning

confidence: 99%

Mechanism of Sulfonylurea Herbicide Resistance in the Broadleaf Weed, Kochia scoparia

Cotterman²,

1990

View full text Add to dashboard Cite

show abstract

“…The substituted 1,2,4-triazolo [1,5-a]pyrimidines are a class of highly active herbicides [1]. Some products such as DE-498, DE-511, and TP have been commercialized.…”

Section: Introductionmentioning

confidence: 99%

Syntheses and biological activities of S‐1,2,4‐triazolo(1,5‐a)pyrimidinylalkyl dithiophosphates

Chen

Jin

2003

Heteroatom Chemistry

View full text Add to dashboard Cite

“…Sulfonylurea herbicides were first discovered by Levitt at Dupont. 2 Fused heterocyclic sulfonamides were the product of a research effort initially aimed at preparing bioisosteric analogues of sulfonylues. Due to the exact 3D-structure target receptor ALS enzyme not being successfully established, it is very difficult to clarify a model of action on the drug receptor, which restrains further research to find any other leading compounds based on the structure of the receptor.…”

Section: Introductionmentioning

confidence: 99%

Three-Dimensional Quantitative Structure−Activity Relationship Analysis of the New Potent Sulfonylureas Using Comparative Molecular Similarity Indices Analysis

Hou

Li²,

Liu³

et al. 2000

J. Chem. Inf. Comput. Sci.

View full text Add to dashboard Cite

The present study describes the implementation of a new three-dimensional quantitative structure-activity relationship (3D-QSAR) technique: comparative molecular similarity indices analysis (CoMSIA) to a set of novel herbicidal sulfonylureas targeted acetolactate synthase. Field expressions in terms of similarity indices in CoMSIA were applied instead of the usually used Lennard-Jones and Coulomb-type potentials in CoMFA. Two different kinds of alignment techniques including field-fit alignment and atom-by-atom fits were used to produce the molecular aggregate. The results indicated that those two alignment rules generated comparative 3D-QSAR models with similar statistical significance. However, from the predictive ability of the test set, the models from the alignment after maximal steric and electrostatic optimization were slightly better than those from the simple atom-by-atom fits. Moreover, systematic variations of some parameters in CoMSIA were performed to search the best 3D-QSAR model. A significant cross-validated q 2 was obtained, indicating the predictive potential of the model for the untested compounds; meanwhile the predicted biological activities of the five compounds in the test set were in good agreement with the experimental values. The CoMSIA coefficient contour plots identified several key features explaining the wide range of activities, which were very valuable for us in tracing the properties that really matter and getting insight into the potential mechanisms of the intermolecular interactions between inhibitor and receptor, especially with respect to the design of new compounds.

show abstract

New herbicidal derivatives of 1,2,4‐triazolo [1,5‐a] pyrimidine

Cited by 84 publications

References 8 publications

Mechanism of Sulfonylurea Herbicide Resistance in the Broadleaf Weed, Kochia scoparia

Mechanism of Sulfonylurea Herbicide Resistance in the Broadleaf Weed, Kochia scoparia

Syntheses and biological activities of S‐1,2,4‐triazolo(1,5‐a)pyrimidinylalkyl dithiophosphates

Three-Dimensional Quantitative Structure−Activity Relationship Analysis of the New Potent Sulfonylureas Using Comparative Molecular Similarity Indices Analysis

Contact Info

Product

Resources

About