. 2022 Apr 8;130(4):047003. doi: 10.1289/EHP9888

Table 6.

Final compound selection: characteristics and in silico selection results.

Chemical name	Abbreviation	CAS number	Use	Purity	Lead criterium^a	QSARs results^b
Benzalkonium chloride	BAC	63449-41-2	PPP: algicide, fungicide	$greater than or equal to 95 percent$	AhR-binding ( $negative 9.5 kilocalories per mole$ )	1/4
Propyl gallate	PG	121-79-9	Additive: antioxidant	$greater than or equal to 98 percent$	AhR-binding ( $negative 7.0 kilocalories per mole$ )	2/4
Paclobutrazol	PBZ	76738-62-0	PPP: plant growth regulator	Not listed	Triadimefon-like (51% similar)	2/4
2-Ethylhexanoic acid	EHA	149-57-5	NIAS-FCM: flavoring agents	$greater than or equal to 98 percent$	VPA-like (91% similar)	3/4
2-Ethyl-1-hexanol	2EH	104-76-7	NIAS-FCM: Flavoring agents, plasticizers	$greater than or equal to 99.6 percent$	VPA-like (67% similar)	4/4
Sodium-dimethyldithiocarbamate	SDC	128-04-1	PPP: microbicide, fungicide	37–43%	Thiram-like (50% similar)	4/4
Sodium-5-nitroguaiacolate	S5N	67233-85-6	PPP: plant growth regulator	$greater than 98 percent$	2,4 Dinitrophenol-like (67% similar)	2/4
Fenpropidin	FEN	67306-00-7	PPP: fungicide	Not listed	Fenpropimorph-like (69% similar)	2/4

Note: AhR, aryl hydrocarbon receptor; BAC, benzalkonium chloride; CAS, Chemical Abstracts Service; 2EH, 2-ethyl-1-hexanol; EHA, 2-ethylhexanoic acid; FEN, fenpropidin; MOA, mode of action; NIAS-FCM, non-intentionally added substances in food contact materials; PBZ, paclobutrazol; PG, propyl gallate; PPP, plant protection product; QSAR, quantitative structure–activity relationship; VPA, valproic acid; S5N, sodium-5-nitroguaiacolate; SDC, sodium-dimethyldithiocarbamate.

^{^a}

The lead criterium for all MOA except AhR binding is structural similarity to the reference compounds in Table 2, with additionally at least two positive QSAR results. The lead criterium for the MOA “AhR binding” (first two substances) is the binding energy to AhR from molecular docking. As the strongest binding substance with at least two positive QSAR predictions showed a relatively low binding energy of $negative 7 kilocalories per mole$ , a very strong predicted AhR binder ( $negative 9.5 kilocalories per mole$ ) was also included in the selection, although it had only one positive QSAR.

^{^b}

Details on the specific QSAR-models predicting positive for the selected compounds are given in Tables S1 and S4.