The first total synthesis of natural 6β-cinnamoyloxy-1α-hydroxy-5, 10-bis-epi- eudesm-4-en-3-one (1), a highly complex natural eudesmane, was described.
Stereocontrolled synthesis of 3(R) and 3(S)-hydroxyeicos-4(E)-en-1-yne has been achieved through double elimination of chloride intermediates 8 and 11, which were prepared from acetylenic alcohol intermediates 1 and 10.
The two diarylheptanoids (E)-1-(4-hydroxy-3-methoxyphenyl)-7-(4-hydroxyphenyl) hept-4-en-3-one 1 (Gingerenone C) and (±)-5-hydroxy-1-(4-hydroxy-3-methoxyphenyl)-7-(4- hydroxyphenyl)-3-heptanone 2 were synthesized...The two diarylheptanoids (E)-1-(4-hydroxy-3-methoxyphenyl)-7-(4-hydroxyphenyl) hept-4-en-3-one 1 (Gingerenone C) and (±)-5-hydroxy-1-(4-hydroxy-3-methoxyphenyl)-7-(4- hydroxyphenyl)-3-heptanone 2 were synthesized from vanillin 3 and 4-hydroxybenzaldehyde 9.展开更多
A facile ndxture of the C-11 isomeric 3 - oxo-7αH-eudes ma-4-en- 9β, 1 2-diol has been achieved ffom oxycarvone. The C-11 configuration of natural product is established through comparison of IHNMR spectra between ...A facile ndxture of the C-11 isomeric 3 - oxo-7αH-eudes ma-4-en- 9β, 1 2-diol has been achieved ffom oxycarvone. The C-11 configuration of natural product is established through comparison of IHNMR spectra between synthatic 1b, or the mixture of 1a and 1b, and natural diol.展开更多
Four stereoisomers of 3,5-bis(2-hydroxybut-3-en-1-yl)-l,2,4-thiadiazole, named insatindigothiadia- zoles A-D (1a-1d), were isolated from the roots oflsatis indigotica. Their structures were determined by spectrosc...Four stereoisomers of 3,5-bis(2-hydroxybut-3-en-1-yl)-l,2,4-thiadiazole, named insatindigothiadia- zoles A-D (1a-1d), were isolated from the roots oflsatis indigotica. Their structures were determined by spectroscopic analysis; specifically, the absolute configurations were assigned by using the MPA determination rule based on △δrs values of MPA esters, and supported by electronic CD (ECD) calculations. Proposed biosynthetic pathways and preliminary investigations of the biological activities of la-1d against influenza virus A (H3N2), Coxsackie virus B3, and/or HSV-1 are also discussed.展开更多
The novel fungicidal agents, (E)-5-[1-(2-oxo-l-oxaspiro[4,5]dec/non-3-en-3-yl)ethylidene]-2-aminoimidazolin- 4-one derivatives, were designed and synthesized in moderate to excellent yields in four steps using a-h...The novel fungicidal agents, (E)-5-[1-(2-oxo-l-oxaspiro[4,5]dec/non-3-en-3-yl)ethylidene]-2-aminoimidazolin- 4-one derivatives, were designed and synthesized in moderate to excellent yields in four steps using a-hydroxyketone and diketene as raw materials and characterized by HR-ESI-MS, 1H NMR and X-ray diffraction. The preliminary bioassay showed that some of these compounds, such as 5e, 6a, 6e, and 7h exhibit 87.8%, 91.3%, 89.9% and 87.8% inhibition rates against Sclerotinia scleotiorum, 3b, 3c, 4c and 7h exhibit 96.4%, 92.5%, 90.3% and 76.9% inhibition rates against Phytophthora capsici at the concentration of 50 μg/mL, respectively. These compounds exhibited significant fungicidal activities against S. scleotiorum and P. capsici with EC50 values of 2.56 --11.60 μg/mL, and compounds 6e and 7h exhibited weak inhibition against the spore germination of S. scleoti- orum, while the spore germination ofP. capsici was strongly inhibited by compound 7h solution. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) observation indicated that compound 7h had a significant impact on the structure and function of the hyphal cell wall ofP. capsici mycelium.展开更多
The increasing medicinal importance of 19-norsteroids, particularly for oral contraceptives, has stimulated intensive research to continuously find more economic methods of either partial and total direct synthesis or...The increasing medicinal importance of 19-norsteroids, particularly for oral contraceptives, has stimulated intensive research to continuously find more economic methods of either partial and total direct synthesis or indirect synthesis via estrone of this class of compound.展开更多
基金This work was financially supported by the National Natural Science Foundation of China (No 20272021).
文摘The first total synthesis of natural 6β-cinnamoyloxy-1α-hydroxy-5, 10-bis-epi- eudesm-4-en-3-one (1), a highly complex natural eudesmane, was described.
文摘Stereocontrolled synthesis of 3(R) and 3(S)-hydroxyeicos-4(E)-en-1-yne has been achieved through double elimination of chloride intermediates 8 and 11, which were prepared from acetylenic alcohol intermediates 1 and 10.
文摘The two diarylheptanoids (E)-1-(4-hydroxy-3-methoxyphenyl)-7-(4-hydroxyphenyl) hept-4-en-3-one 1 (Gingerenone C) and (±)-5-hydroxy-1-(4-hydroxy-3-methoxyphenyl)-7-(4- hydroxyphenyl)-3-heptanone 2 were synthesized from vanillin 3 and 4-hydroxybenzaldehyde 9.
文摘A facile ndxture of the C-11 isomeric 3 - oxo-7αH-eudes ma-4-en- 9β, 1 2-diol has been achieved ffom oxycarvone. The C-11 configuration of natural product is established through comparison of IHNMR spectra between synthatic 1b, or the mixture of 1a and 1b, and natural diol.
基金Financial support from the National Natural Science Foundation of China (Nos. 81373287 and 30825044)the Beijing Excellent Talent Training Project (No. 2013D009008000002)the National Science and Technology Project of China (Nos. 2012ZX09301002002 and 2011ZX09307-002-01)
文摘Four stereoisomers of 3,5-bis(2-hydroxybut-3-en-1-yl)-l,2,4-thiadiazole, named insatindigothiadia- zoles A-D (1a-1d), were isolated from the roots oflsatis indigotica. Their structures were determined by spectroscopic analysis; specifically, the absolute configurations were assigned by using the MPA determination rule based on △δrs values of MPA esters, and supported by electronic CD (ECD) calculations. Proposed biosynthetic pathways and preliminary investigations of the biological activities of la-1d against influenza virus A (H3N2), Coxsackie virus B3, and/or HSV-1 are also discussed.
基金This project was co-tbunded by the Ph.D Program of Ministry of Education, China (No. 20130008110003), and the National Natural Science Foundation of China (No. 21172254).
文摘The novel fungicidal agents, (E)-5-[1-(2-oxo-l-oxaspiro[4,5]dec/non-3-en-3-yl)ethylidene]-2-aminoimidazolin- 4-one derivatives, were designed and synthesized in moderate to excellent yields in four steps using a-hydroxyketone and diketene as raw materials and characterized by HR-ESI-MS, 1H NMR and X-ray diffraction. The preliminary bioassay showed that some of these compounds, such as 5e, 6a, 6e, and 7h exhibit 87.8%, 91.3%, 89.9% and 87.8% inhibition rates against Sclerotinia scleotiorum, 3b, 3c, 4c and 7h exhibit 96.4%, 92.5%, 90.3% and 76.9% inhibition rates against Phytophthora capsici at the concentration of 50 μg/mL, respectively. These compounds exhibited significant fungicidal activities against S. scleotiorum and P. capsici with EC50 values of 2.56 --11.60 μg/mL, and compounds 6e and 7h exhibited weak inhibition against the spore germination of S. scleoti- orum, while the spore germination ofP. capsici was strongly inhibited by compound 7h solution. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) observation indicated that compound 7h had a significant impact on the structure and function of the hyphal cell wall ofP. capsici mycelium.
文摘The increasing medicinal importance of 19-norsteroids, particularly for oral contraceptives, has stimulated intensive research to continuously find more economic methods of either partial and total direct synthesis or indirect synthesis via estrone of this class of compound.