87992-87-8

Upstream product

• 22901-09-3 2-(2-bromoethyl)benzaldehyde 
• 108-42-9 3-chloro-aniline 
• 153333-52-9 1-(2-iodoethyl)-2-(iodomethyl)benzene 
• 1057279-96-5 2-(3-chlorophenyl)-1,2,3,4-tetrahydroisoquinoline 
• 493-05-0 isochromane 

Downstream Products

• 87992-98-1 [2-(3-Chloro-phenyl)-1,2,3,4-tetrahydro-isoquinolin-1-yl]-phosphonic acid diethyl ester 

Relevant academic research and scientific papers

Synthesis of 2-aryl-3,4-dihydroisoquinolin-2-ium bromides and their in Vitro acaricidal activity against Psoroptes cuniculi

By employing sanguinarine, a natural active quaternary isoquinoline alkaloid, as a model molecule, a series of structurally simple quaternary 2-aryl-3,4-dihydroisoquinolin-2-ium compounds were designed and synthesized and evaluated for in vitro acaricidal activity against P. cuniculi. A new approach towards the title compounds was developed with isochroman as starting material. The results showed that 22 of 24 tested compounds displayed the activity in varying degrees at 0.4 mg/mL. Fourteen compounds were significantly more effective than ivermectin, a standard acaricide, and 6-methoxy dihydrosanguinarine, a derivative of sanguinarine (p0.05). And their comprehensive relative activity was 1.4 to 16.5 times than that of ivermectin and 1.5 to 18.8 times than that of 6-methoxy dihydrosanguinarine. The structure-activity relationship indicated that the introduction of a substituent to N-benzene ring, especially halogen atom and trifluoromethyl group, led to great improvement of the activity. The position of fluorine atom, methyl group and hydroxyl group made very significant effects on the activity. It was concluded that 2-aryl-3,4-dihydroisoquinolin- 2-iums are very promising candidates for the development of new isoquinoline acaricidal agents.

2-(substituted phenyl)-3,4-dihydroisoquinolin-2-iums as novel antifungal lead compounds: Biological evaluation and structure-activity relationships

The title compounds are a class of structurally simple analogues of quaternary benzo[c]phenanthridine alkaloids (QBAs). In order to develop novel QBA-like antifungal drugs, in this study, 24 of the title compounds with various substituents on the N-phenylring were evaluated for bioactivity against seven phytopathogenic fungi using the mycelial growth rate method and their SAR discussed. Almost all the compounds showed definite activities in vitro against each of the test fungi at 50 μg/mL and a broad antifungal spectrum. In most cases, the mono-halogenated compounds 2-12 exhibited excellentactivities superior to the QBAs sanguinarine and chelerythrine. Compound 8 possessed the strongest activities on each of the fungi with EC50 values of 8.88-19.88 μg/mL and a significant concentration-dependent relationship. The SAR is as follows: the N-phenyl group is a high sensitive structural moiety for the activity and the characteristics and position of substituents intensively influence the activity. Generally, electron-withdrawing substituents remarkably enhance the activity while electron-donating substituents cause a decrease of the activity. In most cases, ortha- and para-halogenated isomers were more active than the corresponding m-halogenated isomers. Thus, the title compounds emerged as promising lead compounds for the development of novel biomimetic antifungal agrochemicals. Compounds 8 and 2 should have great potential as new broad spectrum antifungal agents for plant protection.

α-Substituted Phosphonates. 43. Synthesis and Reactivity of 1,2,3,4-Tetrahydroisoquinolin-1-phosphonates

N-Alkyl- and N-arylsubstituted 1,2,3,4-tetrahydroisochinolin-1-phosphonates 1 have been synthesized from the corresponding 3,4-dihydroisochinoliniumbromides 7 and triethylphosphite.The N-unsubstituted 1,2,3,4-tetrahydroisochinolin-1-phosphonate 10 is available starting from the 1,2,3,4-tetrahydroisochinolin-1-phosphonic acid by esterification with triethylformate and splitting off the formyl group of the primarily formed N-formyl derivative 14. - N-Quarternated tetrahydroisochinolines 19 and the 1-phosphorylated derivatives 17, respectively react with triethylphosphite in an unexpected way by dealkylation and not by splitting off the isochinolinring. - By Horner-synthesis with 1 the 1-aralkylidene-isochinolines 23 are available in moderate yields.