131929-68-5Relevant articles and documents
A novel semi-synthesis of spinetoram-J based on the selective hydrolysis of 5,6-dihydro spinosyn A
Zhang, Kai,Li, Jiarong,Lamusi
, p. 2801 - 2808 (2019)
Spinetoram is a novel kind of fermentation-derived insecticide with a broad range of action against lots of insect pests. Due to the broad pest spectrum, high insecticidal activity, low environmental impact, and low toxicity to non-target species, spinetoram has been widely applied in pest control and stored-grain protection. Spinetoram is a mixture of spinetoram-J (XDE-175-J, major component) and spinetoram-L (XDE-175-L). In this study, a novel selective hydrolysis of C9-glycosidic bond of 5,6-dihydro spinosyn A was developed. And a 3-step semi-synthesis of spinetoram-J based on the selective hydrolysis was designed and discussed. All compounds in the synthesis were characterized by 1H NMR, 13C NMR and mass spectrum. In addition, the improved semi-synthesis also provides an efficient way to synthesize the rhamnose replacement analogues of spinetoram-J which may be promising in the pest control and fungus control. (Figure presented.).
A semisynthesis of 3′-O-ethyl-5,6-dihydrospinosyn J based on the spinosyn A aglycone
Zhang, Kai,Liu, Shenglan,Liu, Anjun,Chai, Hongxin,Li, Jiarong,Lamusi
, p. 2603 - 2609 (2018/01/17)
Spinetoram, a mixture of 3′-O-ethyl-5,6-dihydrospinosyn J (XDE-175-J, major component) and 3′-O-ethylspinosyn L (XDE-175-L, minor component), is a novel kind of green and efficient insecticide with a broad range of action against various insects. Nowadays, spinetoram is widely used in agriculture and food storage. This work reports a 7-step semisynthesis of 3′-O-ethyl-5,6-dihydrospinosyn J from spinosyn A aglycone. The C9-OH and C17-OH of the aglycone are successively connected to 3-O-ethyl-2,4-di-O-methylrhamnose and D-forosamine after selective protection and deprotection steps. Then, with 10% Pd/C as catalyst, the 5,6-double bond of the macrolide was selectively reduced to afford 3′-O-ethyl-5,6-dihydrospinosyn J. In addition, the 3-O-ethyl-2,4-di-O-methylrhamnose is synthesized from rhamnose which is available commercially, while the D-forosamine and aglycone are obtained via the hydrolysis of spinosyn A. High yields were obtained in each step, and all intermediates in the synthesis were characterized by 1H NMR, 13C NMR and MS techniques. This study can be helpful for developing an efficient chemical synthesis of spinetoram, and it also offers opportunities to synthesize spinosyn analogues and rhamnose derivatives.
Total Synthesis of (-)-Spinosyn A via Carbonylative Macrolactonization
Bai, Yu,Shen, Xingyu,Li, Yong,Dai, Mingji
supporting information, p. 10838 - 10841 (2016/09/12)
Spinosyn A (1), a complex natural product featuring a unique 5,6,5,12-fused tetracyclic core structure, is the major component of spinosad, an organic insecticide and an FDA-approved agent used worldwide. Herein, we report an efficient total synthesis of (-)-spinosyn A with 15 steps in the longest linear sequence and 23 steps total from readily available compounds 14 and 23. The synthetic approach features several important catalytic transformations including a chiral amine-catalyzed intramolecular Diels-Alder reaction to afford 22 in excellent diastereoselectivity, a one-step gold-catalyzed propargylic acetate rearrangement to convert 28 to α-iodoenone 31, an unprecedented palladium-catalyzed carbonylative Heck macrolactonization to form the 5,12-fused macrolactone in one step, and a gold-catalyzed Yu glycosylation to install the challenging β-forosamine. This total synthesis is highly convergent and modular, thus offering opportunities to synthesize spinosyn analogues in order to address the emerging cross-resistance problems.
