3-(diethylamino)-7-imino-7H-[1]benzopyrano[3',2':3,4]pyrido[1,2-a]benzimidazole-6-carbonitrile

Endpoint summary

Description of key information

Adsorption / desorption

KOCWIN model of Estimation Programs Interface was used to predict the soil adsorption coefficient i.e Koc value of test chemical 3 -(diethylamino)-7 -imino-7H-chromeno[3',2':3,4]pyrido [1,2 -a]benzimidazole-6 -carbonitrile (CAS No. 52372 -39 -1). The soil adsorption coefficient i.e Koc value of 3 -(diethylamino)-7 -imino-7H-chromeno [3',2':3,4]pyrido[1,2 -a]benzimidazole-6 -carbonitrile was estimated to be 122500 L/kg (log Koc= 5.0880) by means of MCI method (at 25 deg C). This Koc value indicates that the substance 3 -(diethylamino)-7 -imino-7H-chrome no[3',2':3,4]pyrido[1,2 -a]benzimidazole-6 -carbonitrile has a very strong sorption to soil and sediment and therefore have negligible migration potential to ground water.

Additional information

Adsorption / desorption

Various predicted data for the target compound 3-(diethylamino)-7-imino-7H-chromeno[3',2':3,4]pyrido[1,2-a]benzimidazole-6-carbonitrile (CAS No. 52372-39-1) and supporting weight of evidence study for its structurally and functionally similar read across substance were reviewed for the adsorption end point which are summarized as below:

 

In aprediction done using theKOCWIN Programof Estimation Programs Interface was used to predict the soil adsorption coefficient i.e Koc value of test chemical 3 -(diethylamino)-7 -imino-7H-chromeno[3',2':3,4]pyrido[1,2 -a]benzimidazole-6 -carbonitrile (CAS No. 52372 -39 -1). The soil adsorption coefficient i.e Koc value of 3 -(diethylamino)-7 -imino-7H-chromeno [3',2':3,4]pyrido[1,2 -a]benzimidazole-6 -carbonitrile was estimated to be 122500 L/kg (log Koc= 5.0880) by means of MCI method (at 25 deg C). This Koc value indicates that the substance 3-(diethylamino)-7-imino-7H-chromeno[3',2':3,4]pyrido[1,2-a]benzimidazole-6-carbonitrile has a very strong sorption to soil and sediment and therefore have negligible migration potential to ground water.

 

The Soil Adsorption Coefficient i.e Koc value of test substance 3-(diethylamino)-7-imino-7H-chromeno[3',2':3,4]pyrido[1,2-a]benzimidazole-6-carbonitrile (CAS no. 52372 -39 -1) was estimated using Adsorption Coefficient program as Koc 11.1, 33.8, 65.0, 138, 790, 5553, 15998, 19741, 20215, 20264, 20268 and 20269 at pH range 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 and 11-14 respectively (log Koc value ranges from 1.0 ± 1.0 to 4.3 ± 1.0) (modelling database, 2017). The Koc value (at pH 7.0) indicates that the substance 3 -(diethylamino)-7 -imino-7H-chromeno [3',2':3,4]pyrido[1,2 -a]benzimidazole-6 -carbonitrile has a strong sorption to soil and sediment and therefore have negligible to slow migration potential to ground water.

 

In an another prediction done by using ChemSpider Database (2017), theSoil Adsorption Coefficient i.e Koc value of test substance 3-(diethylamino)-7-imino-7H-chromeno[3',2':3,4]pyrido[1,2-a]benzimidazole-6-carbonitrile (CAS no. 52372 -39 -1) was estimated. The adsorption coefficient (Koc) value of test substance 3 -(diethylamino)-7 -imino-7H-chromeno[3',2':3,4]pyrido[1,2 -a]benzimidazole-6 -carbonitrile was estimated to be 7136.58 (Log Koc = 3.853) at pH 5.5 and 12565.31 (Log Koc = 4.099) at 7.4, respectively. This Koc value indicates that the substance 3 -(diethylamino)-7 -imino-7H-chromeno[3',2':3,4]pyrido[1,2 -a]benzimidazole-6 -carbonitrile has a strong sorption to soil and sediment and therefore have negligible to slow migration potential to ground water.

 

Additional soil adsorption coefficient i.e Koc value of test chemical3 -(diethylamino)-7 -imino-7H-chrom eno[3',2':3,4]pyrido[1,2 -a]benzimidazole-6 -carbonitrile (CAS No. 52372 -39 -1)was estimated using the SciFinder database (2017).The soil adsorption coefficient i.e Koc value of 3 -(diethylamino)-7 -imino-7H-chromeno[3',2':3,4] pyrido[1,2 -a]benzimidazole-6 -carbonitrile was estimated to be 1070, 2580, 5680, 31900, 228000, 684000, 858000, 880000, 882000 and 883000 at pH range 1, 2, 3, 4, 5, 6, 7, 8, 9 and 10, respectively (at 25 deg C) (log Koc value ranges from 3.029 to 5.945). The Koc value (at pH 7.0) indicates that the substance 3 -(diethylamino)-7 -imino-7H- chromeno[3',2':3,4]pyrido[1,2 -a]benzimidazole-6 -carbonitrile has a very strong sorption to soil and sediment and therefore have negligible migration potential to ground water.

 

From CompTox Chemistry Dashboard using OPERA (OPEn (quantitative) structure-activity Relationship Application) model in which calculation based on PaDEL descriptors (calculate molecular descriptors and fingerprints of chemical), the adsorption coefficient i.e KOC for test substance 3 -(diethylamino)-7 -imino-7H-chromeno[3',2':3,4]pyrido[1,2 -a]benzimidazole-6 -carbonitrile was estimated to be 135000 L/kg (log Koc = 5.13).The predicted KOC result based on the 5 OECD principles. This Koc value indicates that the substance 3-(diethylamino)-7-imino-7H-chromeno[3',2':3,4]pyrido[1,2-a]benzimidazole-6-carbonitrile has a very strong sorption to soil and sediment and therefore have negligible migration potential to ground water.

 

In a supporting weight of evidence study from study report (2018) for the test item,the adsorption coefficient Koc in soil and in sewage sludge of test chemical was determined by the Reverse Phase High Performance Liquid Chromatographic method according to OECD Guideline No. 121 for testing of Chemicals. The solutions of the test substance and reference substances were prepared in appropriate solvents. A test item solution was prepared by accurately weighing 50mg of test item and diluted with mobile phase up to 100ml. Thus, the test solution concentration was 500mg/l. The pH of test substance was 7.90. Each of the reference substance and test substance were analysed by HPLC at 210 nm. After equilibration of the HPLC system, Urea was injected first, the reference substances were injected in duplicate, followed by the test chemical solution in duplicate. Reference substances were injected again after test sample, no change in retention time of reference substances was observed. Retention time tR were measured, averaged and the decimal logarithms of the capacity factors k were calculated. The graph was plotted between log Koc versus log k(Annex - 2).The linear regression parameter of the relationship log Koc vs log k were also calculated from the data obtained with calibration samples and therewith, log Koc of the test substance was determined from its measured capacity factor. T The reference substances were chosen according to structural similarity with the test substance and calibration graph was prepared. The reference substances were 4 – Toluidine, N-methylaniline, Toluene, Naphthalene, Phenanthrene and DDDT having Koc value ranging from 1.9 to 5.63.The Log Koc value of test chemical was determined to be 3.594 ± 0.003 at 25°C. This log Koc value indicates that the test substance has a strong sorption to soil and sediment and therefore have negligible to slow migration potential to ground water.

 

On the basis of above overall results for target chemical 3-(diethylamino)-7-imino-7H-chromeno[3',2':3,4]pyrido[1,2-a]benzimidazole-6-carbonitrile (from modelling databases,2017), it can be concluded that the Koc value of test substance 3-(diethylamino)-7-imino-7H-chromeno[3',2':3,4]pyrido[1,2-a]benzimidazole-6-carbonitrile was estimated to be 12565.31 to 858000.0 (logKoc ranges from 4.099 to 5.933 at pH 7.0) indicating that the test chemical 3-(diethylamino)-7-imino-7H-chromeno[3',2':3,4]pyrido[1,2-a]benzimidazole-6-carbonitrile has a strong to very strong sorption to soil and sediment and therefore have negligible to slow migration potential to ground water.