Design, synthesis, and biological evaluation of novel substituted thiourea derivatives as potential anticancer agents for NSCLC by blocking K-Ras protein-effectors interactions

Figures & data

Figure 1. Three reported compounds targeting K-Ras^G12V protein.

Scheme 1. (a) MeONa, MeOH, rt; (b) NH₂NH₂, MeOH; (c) CS₂, TEA, THF, rt; (d) Boc₂O, DMAP, 5 °C to rt; (e) C, CH₃CN, TEA, rt. R₁ = (o-tolyl)/(p-tolyl)/(3-chlorophenyl)/(2-chlorophenyl)/(4-(trifluoromethyl)phenyl)/(naphthalen-1-yl)/(3,5-dimethylphenyl); R₂ = (2,6-dinitro-4-(trifluoromethyl)phenyl).

Scheme 2. (f) BTC, TEA, EA, 50 °C; (g) C, CH₃CN, TEA, rt. R₁ = 4-(trifluoromethyl)phenyl)/(3-chloro-4-methylphenyl); R₂ = (2,6-dinitro-4-(trifluoromethyl)phenyl).

Scheme 3. (h) G, CH3CN, TEA, rt; (i) E, CH3CN, TEA, rt. R₁ = 4-(trifluoromethyl)phenyl)/(3-chloro-4-methylphenyl); R₂ = mesitylene/4-(trifluoromethyl)phenyl)/(1,1′-biphenyl)/(3s,5s,7s)-adamantan-1-yl)/(4-phenoxyphenyl).

Scheme 4. (j) DCM, TEA, 1–5 °C; (k) HCl, H₂O, CH₃COOH, 1–5 °C; (l) NaNO₂/H₂O, 1–5 °C. R₃ = 4-(trifluoromethyl)phenyl)/(3-chloro-4-methylphenyl).

Table 1. Compounds TKR01-TKR07 and their anti-tumour activity.

Compound	R1	R2	R3	R4	IC50 (μM)
Sorafenib	–	–	–	–	8.50
TKR01	–CH3	–H	–H	–H	101.7
TKR02	–H	–H	–CH3	–H	>100
TKR03	–H	–Cl	–H	–H	2.72
TKR04	–Cl	–H	–H	–H	>100
TKR05	–H	–H	–CF3	–H	1.25
TKR06	Naphthalene	Naphthalene	–H	–H	>100
TKR07	–H	–CH3	–H	–CH3	>100

Table 2. Compounds TKR08-TKR09 and their anti-tumour activity.

Compound	R4	R5	IC50 (μM)
TKR08	–Cl	–CH3	125.9
TKR09	–H	–CF3	81.9

Table 3. Compounds TKR10–TKR18 and their anti-tumour activity.

Table 4. Compounds TKR19–TKR21 and their anti-tumour activity.

Compound	R9	X	R10	IC50 (μM)
TKR19	–CH3	O	–Cl	>100
TKR20	–CF3	O	–H	22.75
TKR21	–CF3	S	–H	18.57

Figure 2. (A) Cartoon structure and (B) Surface structure of molecular docking analysis of small molecule TKR15 and K-Ras^G12V protein.

Figure 3. (A) Flow cytometric analysis of compound TKR-15 induced apoptosis on A549 cells; (B) Cell apoptosis amount of A549 after treating TKR15 and Sorafenib (the results were significant, p < 0.05, n = 3).

Figure 4. Immunostaining of A549 after treatment with compound TKR15 for 2 h (20 μM). The vehicle control for the above experiments was 0.1% DMSO.