Synthesis, Fungicidal Activity, and Structure−Activity Relationship of Spiro-Compounds Containing Macrolactam (Macrolactone) and Thiadiazoline Rings

• Published in: Journal of agricultural and food chemistry 2010-03, Vol.58 (5), p.2659-2663
• Main Authors: Li, Jian-Jun, Liang, Xiao-Mei, Jin, Shu-Hui, Zhang, Jian-Jun, Yuan, Hui-Zhu, Qi, Shu-Hua, Chen, Fu-Heng, Wang, Dao-Quan
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; Food industries; Fundamental and applied biological sciences. Psychology; Fungi - drug effects; Fungicides, Industrial - chemical synthesis; Fungicides, Industrial - chemistry; Fungicides, Industrial - pharmacology; Hydrogen Bonding; Lactams - chemical synthesis; Lactams - chemistry; Lactams - pharmacology; Magnetic Resonance Spectroscopy; Molecular Structure; Structure-Activity Relationship; Thiadiazoles - chemical synthesis; Thiadiazoles - chemistry; Thiadiazoles - pharmacology
• ISSN: 0021-8561; 1520-5118
• DOI: 10.1021/jf903665f

Two series of novel spiro-compounds containing macrolactam or macrolactone and thiadiazoline rings, 1-thia-2-alkylimino-3,4,9-triaza-10-oxospiro[4.15]eicosyl-3-ene (4F) and 1-thia-2-alkylimino-3,4-diaza-9-oxa-10-oxospiro[4.15]eicosyl-3-ene (4G), were synthesized from 12-oxo-1,15-pentadecanlactam and 12-oxo-1,15-pentadecanlactone, respectively. Their structures were confirmed by elemental analysis, 1H NMR, and 13C NMR. The conformation of compounds 4F was determined via the crystal structure of a representative compound (4F6 ). The bioassay showed that compounds 4F have much better fungicidal activity against five fungi (Botrytis cinerea Pers., Sclerotinia sclerotiorum, Rhizoctonia solani Kühn., Phomopsis asparagi Sacc., and Pyricularia oryzae Cav.) than compounds 4G. The fact above showed that the presence of a hydrogen-bonding donor for the fungicidal activity of macrocyclic compounds is very important. 4F6 showed excellent fungicidal activity against P. oryzae, which is much better than the commercial fungicide isoprothiolane, and 4F13 showed excellent fungicidal activity against P. oryzae and good fungicidal activity against P. asparagi.