Chemical and Cytotoxic Constituents from the Stem of Machilus zuihoensis

Five new compounds, including a novel lactone, machilactone (=rel‐(2R,3aR,6E,6aS)‐2‐heptadecyl‐3a‐methyl‐6‐octadecylidene‐6,6a‐dihydrofuro[2,3‐d][1,3]dioxol‐5(3aH)‐one; 1 ), a new sesquiterpene, 3,4‐dihydroxy‐β‐bisabolol (=rel‐(1R,2S,4R)‐1‐[(1R)‐1,5‐dimethylhex‐4‐enyl]‐1‐methylcyclohexane‐1,2,4‐triol; 2 ), a new secobutyrolactone, methyl (2E)‐2‐(1‐hydroxy‐2‐oxopropyl)eicos‐2‐enoate ( 3 ), two new butyrolactones, machicolide A ( 4 ) and machicolide B ( 5 ) (=3E,4R,5R)‐ and (3Z,4R,5R)‐4,5‐dihydro‐4‐hydroxy‐5‐methoxy‐5‐methyl‐3‐octadecylidenefuran‐2(3H)‐one, resp.) as a mixture, together with known caryophyllene oxide (=4,12,12‐trimethyl‐9‐methylene‐5‐oxatricyclo[8.2.0.0^4,6]dodecane), hexacosane, tetracosanoic acid, isomahubanolide‐23 (=(3E,4R)‐4,5‐dihydro‐4‐hydroxy‐5‐methylidene‐3‐octadecylidenefuran‐2(3H)‐one), and β‐bisabolol (=(1S)‐1‐[(1S)‐1,5‐dimethylhex‐4‐enyl]‐4‐methylcyclohex‐3‐en‐1‐ol) were isolated from the stem wood of Machilus zuihoensis. The structures of these compounds were established by spectroscopic studies. The eicos‐2‐enoate ( 3 ) and β‐bisabolol exhibited marginal cytotoxicity against NUGC and HONE‐1 cancer cell lines in vitro.     

Isolation of a New Carotenoid and Two New Carotenoid Glycosides from Curtobacterium flaccumfaciens pvar poinsettiae

An efficient method for the extraction of the carotenoids from Curtobacterium flaccumfaciens pvar poinsettiae was developed. The glucosides of C.p. 450 (=(all‐E,2R,2′R)‐2‐[4‐(β‐D ‐glucopyranosyloxy)‐3‐methylbut‐2‐enyl]‐2′‐(4‐hydroxy‐3‐methylbut‐2‐enyl)‐β, β‐carotene; 4 ) and of C.p. 473 (=(all‐E,2R,2′S)‐2‐[4‐(β‐D ‐glucopyranosyloxy)‐3‐methylbut‐2‐enyl]‐2′‐(3‐methylbut‐2‐enyl)‐3′,4′‐didehydro‐1′,2′‐dihydro‐β,ψ‐caroten‐1′‐ol; 5 ) were isolated for the first time. In addition, the hitherto unknown 3′,4′‐dihydro derivative of C.p. 450, called C.p. 460 (=(all‐E,2R,2′R)‐2‐(4‐hydroxy‐3‐methylbut‐2‐enyl)‐2′‐(3‐methylbut‐2‐enyl)‐1′,2′‐dihydro‐β,ψ‐caroten‐1′‐ol; 6 ), was identified. The structures were established by UV/VIS, CD, ¹H‐ and ¹³C‐NMR, and mass spectra.     

Scyphiphorins A and B,Two New Iridoid Glycosides from the Stem Bark of a Chinese Mangrove Scyphiphora hydrophyllacea

Two new iridoid glycosides, named scyphiphorins A ( 1 ) and B ( 2 ), together with four known compounds, geniposidic acid (=(1S,4aS,7aS)‐1‐(β‐D ‐glucopyranosyloxy)‐1,4a,5,7a‐tetrahydro‐7‐(hydroxymethyl)cyclopenta[c]pyran‐4‐carboxylic acid; 3 ), 4‐(4‐hydroxy‐3‐methoxybenzyl)butan‐2‐one, oleanolic acid (=(3β)‐3‐hydroxyolean‐12‐en‐28‐oic acid), and stigmasterol β‐D ‐glucoside (=(3β,22E)‐stigmasta‐5,22‐dien‐3‐yl β‐D ‐glucopyranoside), were isolated for the first time from the stem bark of a Chinese mangrove, Scyphiphora hydrophyllacea Gaertn . f. The structures of compounds 1 and 2 were determined as 10‐O‐benzoylgeniposidic acid and 10‐O‐[(2E,6R)‐8‐hydroxy‐2,6‐dimethyl‐1‐oxooct‐2‐en‐1‐yl]geniposidic acid, respectively, on the basis of spectroscopic data and chemical methods, including 2D NMR techniques.     

Two New Highly Oxidized Humulane Sesquiterpenes from the Basidiomycete Lactarius mitissimus

Two new highly oxidized humulane sesquiterpenes, mitissimols F ( 1 ) and G ( 2 ), were isolated from the fruiting bodies of Lactarius mitissimus. Their structures were elucidated by using extensive spectroscopic techniques including 1D‐ and 2D‐NMR experiments. The absolute configuration of mitissimol F ( 1 ) was determined by ¹H‐NMR resolution of its diastereoisomeric α‐methoxy‐α‐(trifluoromethyl)benzeneacetates (MTPA). It was shown to be (1S,3E,6S,8R,9R,10S,11R)‐8,9 : 10,11‐diepoxy‐1,6‐dihydroxyhumul‐3‐en‐5‐one (=(1S,2R,4R,6S,8E,11S,12R)‐6,11‐dihydroxy‐1,6,10,10‐tetramethyl‐3,13‐dioxatricyclo[10.1.0.0^2,4]tridec‐8‐en‐7‐one).     

Preparation and (E/Z)‐Isomerization of the Diastereoisomers of Violaxanthin

Violaxanthin A (=(all‐E,3S,5S,6R,3′S,5′S,6′R)‐5,6 : 5′,6′‐diepoxy‐5,6,5′,6′‐tetrahydro‐β,β‐carotene‐3,3′‐diol =syn,syn‐violaxanthin; 5 ) and violaxanthin B (=(all‐E,3S,5S,6R,3′S,5′R,6′S)‐5,6 : 5′,6′‐diepoxy‐5,6,5′,6′‐tetrahydro‐β,β‐carotene‐3,3′‐diol=syn,anti‐violaxanthin; 6 ) were prepared by epoxidation of zeaxanthin diacetate ( 1 ) with monoperphthalic acid. Violaxanthins 5 and 6 were submitted to thermal isomerization and I₂‐catalyzed photoisomerization. The structure of the main products, i.e., (9Z)‐ 5 , (13Z)‐ 5 , (9Z)‐ 6 , (9′Z)‐ 6 , (13Z)‐ 6 , and (13′Z)‐ 6 , was determined by their UV/VIS, CD, ¹H‐NMR, ¹³C‐NMR, and mass spectra.     

Three New Neolignans from the Aril of Myristica fragrans

Three new neolignans, named 1‐deoxycarinatone ( 1 ), isodihydrocarinatidin ( 2 ), and isolicarin A ( 3 ), together with the known neolignan (+)‐dehydrodiisoeugenol ( 4 ), were isolated from mace (the aril of Myristica fragrans Houtt .). Their structures were elucidated as 2‐[(1S)‐2‐(4‐hydroxy‐3‐methoxyphenyl)‐1‐methylethyl]‐6‐methoxy‐4‐(prop‐2‐enyl)phenol ( 1 ), 4‐[(2R,3R)‐2,3‐dihydro‐7‐methoxy‐3‐methyl‐5‐(prop‐2‐enyl)benzofuran‐2‐yl]‐2‐methoxyphenol ( 2 ), and 4‐{(2S,3R)‐2,3‐dihydro‐7‐methoxy‐3‐methyl‐5‐[(1E)‐prop‐1‐enyl]benzofuran‐2‐yl}‐2‐methoxyphenol ( 3 ) on the basis of spectroscopic data.     

Isomerization of (all‐E)‐Cucurbitaxanthin A

Cucurbitaxanthin A (=(all‐E,3S,5R,6R,3′R)‐3,6‐epoxy‐5,6‐dihydro‐β,β‐carotene‐5,3′‐diol; 1 ) was submitted to thermal isomerization and to I₂‐catalysed photoisomerization. The structure of the main reaction products (9Z)‐ ( 2 ), (9′Z)‐ ( 3 ), (13Z)‐ ( 4 ), and (13′Z)‐cucurbitaxanthin A ( 5 ) was determined by their UV/VIS, CD, ¹H‐NMR, and mass spectra.     

Dolabellane Diterpenoids from the Higher Plant Aglaia odorata

Two new dolabellane diterpenoids, (1R,3R,7E,11S,12R)‐dolabella‐4(16),7‐diene‐3,18‐diol ( 1 ) and (1R,3E,7R,11S,12R)‐dolabella‐3,8(17)‐diene‐7,18‐diol ( 2 ), and the known (1R,3E,7E,11S,12R)‐dolabella‐3,7‐dien‐18‐ol ( 3 ) were isolated from Aglaia odorata, along with twelve other known compounds. Their structures were elucidated on the basis of spectroscopic data. This is the first time that dolabellane‐type diterpenoids were detected in higher plants.     

New Nonhydrolyzable Mimetics of Sialyl Lewis X and Their Binding Affinity to P‐Selectin

Wittig olefination of (2S,3R,5S,6R)‐5‐(acetyloxy)‐tetrahydro‐6‐[(methoxymethoxy)methyl]‐3‐(phenylthio)‐ 2H‐pyran‐2‐acetaldehyde ((+)‐ 10 ) with {2‐[(2S,3R,4R,5R,6S)‐tetrahydro‐3,4,5‐tris(methoxymethoxy)‐6‐methyl‐ 2H‐pyran‐2‐yl]ethyl}triphenylphosphonium iodide ((?)‐ 11 ) gave a (Z)‐alkene derivative (+)‐ 12 that was converted into (αR,2R,3S,4R,5R,6S)‐tetrahydro‐α,3‐dihydroxy‐2‐(hydroxymethyl)‐5‐(phenylthio)‐6‐{(2Z)‐4‐[(2S,3S,4R,5S,6S)‐tetrahydro‐3,4,5‐trihydroxy‐6‐methyl‐2H‐pyran‐2‐yl]but‐2‐enyl}2H‐pyran‐4‐acetic acid ( 8 ), (αR,2R,3S,4R,6S)‐tetrahydro‐α,3‐dihydroxy‐2‐(hydroxymethyl)‐6‐{4‐[(2S,3S,4R,5S,6S)‐tetrahydro‐3,4,5‐trihydroxy‐6‐methyl‐2H‐pyran‐2‐yl]butyl}‐2H‐pyran‐4‐acetic acid ( 9 ), and simpler analogues without the hydroxyacetic side chain such as (2S,3S,4R,5S,6S)‐tetrahydro‐6‐methyl‐2‐{(2Z)‐4‐[(2S,3R,5S,6R)‐tetrahydro‐5‐hydroxy‐6‐(hydroxymethyl)‐3‐(phenylthio)‐2H‐pyran‐2‐yl]but‐2‐enyl}‐2H‐pyran‐3,4,5‐triol ( 30 ), (2S,3S,4R,5S,6S)‐tetrahydro‐6‐methyl‐2‐{[(2S,5S,6R)‐tetrahydro‐5‐hydroxy‐6‐(hydroxymethyl)‐2H‐pyran‐2‐yl]butyl}‐2H‐pyran‐3,4,5‐ triol ((?)‐ 41 ) and (2S,3S,4R,5S,6S)‐tetrahydro‐6‐methyl‐2‐{(2Z/E))‐4‐[(2R,5S,6R)‐tetrahydro‐5‐hydroxy‐6‐(hydroxymethyl)‐2H‐pyran‐2‐yl]but‐2‐enyl}‐2H‐pyran‐3,4,5‐triol ( 43 ). The key intermediates (+)‐ 10 and (?)‐ 11 were derived from isolevoglucosenone and from L ‐fucose, respectively. The following IC₅₀ values were measured in a ELISA test for the affinities of sialyl Lewis x tetrasaccharide, 8, 9, 30 , (?)‐ 41 , and 43 toward P‐selectin: 0.7, 2.5–2.8, 7.3–8.0, 5.3–5.9, 5.0–5.2, and 3.4–4.1 mM , respectively.     

A Guaianolide Sesquiterpene,a Chromenone,and a Flavanone from Ligularia macrophylla

Three new compounds, (5β,9β)‐guaia‐6,10(14)‐dien‐9‐ol (=rel‐(1R,3aS,5R,8aR)‐1,2,3,3a,4,5,6,8a‐octahydro‐1‐methyl‐4‐methylene‐7‐(1‐methylethyl)azulen‐5‐ol; 1 ), 6‐acetyl‐8‐methoxy‐2,3‐dimethylchromen‐4‐one (=6‐acetyl‐8‐methoxy‐2,3‐dimethyl‐4H‐1‐benzopyran‐4‐one; 2 ), and (2S)‐3′‐hydroxy‐5′,7‐dimethoxyflavanone (=(2S)‐2,3‐dihydro‐2‐(3‐hydroxy‐5‐methoxyphenyl)‐7‐methoxy‐4H‐1‐benzopyran‐4‐one; 3 ) were isolated from the roots and rhizomes of Ligularia macrophylla, together with seven known compounds. Their structures and configurations were elucidated by spectroscopic methods, including 2D‐NMR techniques.     

Partial Synthesis and Characterization of Karpoxanthins and Cucurbitaxanthin A Epimers

Karpoxanthin (=(all-E,3S,5R,6R,3′R)-5,6-dihydro-β,β-carotene-3,5,6,3′-tetrol; 7 ), 6-epikarpoxanthin (=(all-E,3S,5R,6S,3′R)-5,6-dihydro-β,β-carotene-3,5,6,3′-tetrol; 4 ), 5-epikarpoxanthin (=(all-E,3S,5S,6R,3′-R)-5,6-dihydro-β,β-carotene-3,5,6,3′-tetrol; 11 ), cucurbitaxanthin A (=(all-E,3S,5R,6R,3′R)-3,6-epoxy-5,6-dihydro-β,β-carotene-5,3′-diol; 10 ), epicucurbitaxanthin A (=(all-E-3S,5S,6R,3′R)-3,6-epoxy-5,6-dihydro-β,β-carotene-5,3′-diol; 14 ), and the corresponding mutatoxanthin epimers 8 , 9 , 12 , and 13 were prepared in crystalline state by the acid-catalyzed hydrolysis of (3S,5R,6S,3′R)- and (3S,5S,6R,3′R)-antheraxanthin ( 5 and 6 , resp.) and characterized by their UV/VIS, CD, ¹H- and ¹³C-NMR, and mass spectra.     

Chemical Constituents of the Flowers of Azadirachta indica

Studies on the chemical constituents of the flowers of Azadirachta indica have led to the isolation of two new flavanones, flowerine (=5‐hydroxy‐7,4′‐dimethoxy‐8‐(3‐methylbut‐2‐enyl)flavan‐4‐one; 1 ) and flowerone (=5,7,8,4′‐tetrahydroxy‐3′‐(3‐methylbut‐3‐enyl)flavan‐4‐one; 2 ), and two new triterpenoids, O‐methylazadironolide (=7α‐(acetoxy)‐23ξ‐methoxy‐21,23‐epoxy‐24,25,26,27‐tetranorapotirucalla‐1,14,20(22)‐trien‐3,21‐dione; 3 ) and diepoxyazadirol (=(20S,23S,24R)‐7‐α‐(acetoxy)‐25‐hydroxy‐21,24 : 23,24‐diepoxyapotirucalla‐1,14‐dien‐3‐one; 4 ) along with the known triterpenoid trichilenone acetate (=7α‐(acetoxy)‐14,15 : 21,23‐diepoxy‐24,25,26,27‐tetranorapotirucalla‐1,20,22‐trien‐3‐one; 5 ), two known flavanones, nimbaflavone (=5,7‐dihydroxy‐4′‐methoxy‐8,3′‐bis(3‐methylbut‐2‐enyl)‐flavan‐4‐one; 6 ) and 3′‐prenylnaringenin (=5,7,4′‐trihydroxy‐3′‐(3‐methylbut‐2‐enyl) flavan‐4‐one; 7 ), and 4‐(2‐hydroxyethyl)phenol ( 8 ). Their structures have been elucidated through spectral studies, including 2D‐NMR experiments, and chemical transformation. Compounds 5, 7 and 8 are heretofore unreported from any part of tree, while 6 has been isolated earlier from leaves.     

(E/Z)‐Isomerization of 3′‐Epilutein

3′‐Epilutein (=(all‐E,3R,3′S,6′R)‐4′,5′‐didehydro‐5′,6′‐dihydro‐β,β‐carotene‐3,3′‐diol; 1 ), isolated from the flowers of Caltha palustris, was submitted to both thermal isomerization and I₂‐catalyzed photoisomerization. The structures of the main products (9Z)‐ 1 , (9′Z)‐ 1 , (13Z)‐ 1 , (13′Z)‐ 1 , (15Z)‐ 1 , and (9Z,9′Z)‐ 1 were determined based on UV/VIS, CD, ¹H‐NMR, and MS data.     

Sterols from the Stems of Momordica charantia

A new sterol, 5α,6α‐epoxy‐3β‐hydroxy‐(22E,24R)‐ergosta‐8,22‐dien‐7‐one ( 1 ), together with eight known sterols, 5α,6α‐epoxy‐(22E,24R)‐ergosta‐8,22‐diene‐3β,7α‐diol ( 2 ), 5α,6α‐epoxy‐(22E,24R)‐ergosta‐8,22‐diene‐3β,7β‐diol ( 3 ), 5α,6α‐epoxy‐(22E,24R)‐ergosta‐8(14),22‐diene‐3β,7α‐diol ( 4 ), 3β‐hydroxy‐(22E,24R)‐ergosta‐5,8,22‐trien‐7‐one ( 5 ), ergosterol peroxide ( 6 ), clerosterol ( 7 ), decortinol ( 8 ), and decortinone ( 9 ), were isolated from the stems of Momordica charantia. Their structures were elucidated by mean of extensive spectroscopic methods, including ¹H, ¹³C, 2D‐NMR and HR‐EI‐MS, as well as comparison with the literature data. Compounds 1 , 4 , 5 , 8 , and 91 were not cytotoxic against the SK‐Hep 1 cell line.     

Three New Neolignans and One New Phenylpropanoid from the Leaves and Stems of Toona ciliata var. pubescens

Three new neolignans, (7S,8S,7′E)‐4,9‐dihydroxy‐3,7,3′,9′‐tetramethoxy‐8,4′‐oxyneolign‐7′‐ene ( 1 ), (7R,8S,7′E)‐4, 9‐dihydroxy‐3,7,3′,9′‐tetramethoxy‐8,4′‐oxyneolign‐7′‐ene ( 2 ), (7S,8S,7′E)‐5, 9‐dihydroxy‐3,7,3′,5′,9′‐pentamethoxy‐8,4′‐oxyneolign‐7′‐ene ( 3 ), and one new phenylpropanoid, threo‐5‐hydroxy‐3,7‐dimethoxyphenylpropane‐8,9‐diol ( 4 ), were isolated from the leaves and stems of Toona ciliata var. pubescens. Their structures were determined on the basis of spectroscopic analysis, especially 2D‐NMR, HR‐ESI‐MS, and CD data. The antiproliferative activities of these compounds against four tumor cell lines (A549, Colo 205, QGY‐7703, and LOVO) were also evaluated by MTT (=(3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyl‐2H‐tetrazolium bromide) method.     

Reduction of Capsorubin and Cryptocapsin

(6′S)‐ and (6′R)‐‘Capsorubol‐6‐one' (=(3S,3′S,5R,5′R,6′S)‐ and (3S,3′S,5R,5′R,6′R)‐3,3′,6′‐trihydroxy‐κ,κ‐caroten‐6‐one; 8 and 9 , resp.), (6S,6′R)‐ and (6R,6′R)‐capsorubol (=3S,3′S,5R,5′R,6S,6′R)‐ and (3S,3′S,5R,5′R,6R,6′R)‐κ,κ‐carotene‐3,3′,6,6′‐tetrol; 11 and 12 , resp.) and (6′S)‐ and (6′R)‐cryptocapsol (=(3′S,5′R,6′S)‐ and (3′S,5′R,6′R)‐β,κ‐carotene‐3′,6′‐diol; 5 and 6 , resp.) were prepared in crystalline from by the reduction of capsorubin (=(3S,3′S,5R,5′R)‐3,3′‐dihydroxy‐κ,κ‐carotene‐6,6′‐dione; 7 ) and cryptocapsin (=(3′S,5′R)‐3′‐hydroxy‐β,κ‐caroten‐6′‐one; 4 ) and characterized by their UV/VIS, CD, ¹H‐NMR, and mass spectra.     

Hydrolytic Reaction of Plant Extracts to Generate Molecular Diversity: New Dammarane Glycosides from the Mild Acid Hydrolysate of Root Saponins of Panax notoginseng

Molecular diversity was generated by hydrolyzing the crude root saponins of Panax notoginseng (Burk .) F. H. Chen under mild acidic condition (AcOH/EtOH 1 : 1). From the acid hydrolysate, five new dammarane glycosides, named notoginsenoside T₁ (=(3β,6α,12β,20E,23RS)‐24,25‐epoxy‐6‐[(β‐D ‐glucopyranosyl)oxy]‐dammar‐20(22)‐ene‐3,12,23‐triol; 1 ), notoginsenoside T₂ (=(3β,6α,12β,20E,23RS)‐24,25‐epoxy‐6‐[(β‐D ‐glucopyranosyl)oxy]‐23‐methoxydammar‐20(22)‐ene‐3,12‐diol; 2 ), notoginsenoside T₃ (=(3β,6α,12β,20S)‐6‐[(β‐D ‐glucopyranosyl)oxy]‐20‐ethoxydammar‐24‐ene‐3,12‐diol; 3 ), notoginsenoside T₄ (=(3β,6α,12β,20S,22E,24RS)‐6‐[(β‐D ‐glucopyranosyl)oxy]dammar‐22‐ene‐3,12,20,24,25‐pentol; 4 ), and notoginsenoside T₅ (=(3β,6α,12β, 24E)‐6‐[(β‐D ‐xylopyranosyl‐(1→2)‐β‐D ‐glucopyranosyl)oxy]dammara‐20(21),24‐diene‐3,12‐diol; 5 ), were isolated, together with 15 known dammarane glycosides, and their structures were elucidated on the basis of spectroscopic evidence. Among the known compounds, ginsenosides Rg₃ and Rh₁ were isolated as major constituents, in addition to ginsenosides Rg₅, Rh₄, and a mixture of (20R)‐ and (20S)‐25‐hydroxyginsenoside Rh₁, all of which were obtained from P. notoginseng for the first time.     

Diterpene Glycosides from the Dry Fronds of Conyza japonica

Phytochemical investigation of the 95% EtOH extract of the dry fronds of Conyza japonica (Thunb .) Less. resulted in the isolation of three new labdane diterpene glycosides, (3β,13S)‐13‐O‐α‐L ‐rhamnopyranosyllabda‐8(17),14‐dien‐3‐yl α‐L ‐rhamnopyranoside ( 1 ), (3β,13S)‐13‐O‐α‐L ‐rhamnopyranosyllabda‐8(17),14‐diene‐3‐yl 2‐O‐acetyl‐α‐L ‐rhamnopyranoside ( 2 ), and (3β,13S)‐13‐O‐α‐L ‐rhamnopyranosylabda‐8(17),14‐dien‐3‐yl 6‐O‐acetyl‐β‐D ‐glucopyranosyl‐(1→2)‐α‐L ‐rhamnopyranoside ( 3 ), together with their aglycone, (13S)‐labda‐8(17),14‐diene‐3,13‐diol ( 4 ). Their structures were characterized by spectroscopic analyses and chemical correlations, including 1D‐ and 2D‐NMR, and HR‐ESI‐MS. Furthermore, compounds 1 – 3 appeared to be promising as active agents against the tested pathogen fungi and oral pathogens as they possessed moderate cytotoxic properties.     

A Rare New Cleistanthane Diterpene from the Pericarp of Trewia nudiflora

A minor, unprecedented diterpene, 3β,17‐dihydroxycleistantha‐12,15‐dien‐2‐one ( 1 ), was isolated from the CHCl₃‐soluble part of the EtOH extract of the pericarp of Trewia nudiflora. The structure of 1 was elucidated by means of 1D‐ and 2D‐NMR spectroscopic analyses as well as by HR‐MS. Also isolated were two known triterpenes, glutin‐5‐en‐3‐ol and olean‐18‐en‐3‐one (germanicone), as well as three known sterols, (22E,24R)‐5α,8α‐epidioxyergosta‐6,22‐dien‐3β‐ol, (22E,24R)‐5α,8α‐epidioxyergosta‐6,9(11),22‐trien‐3β‐ol, and (22E,24R)‐6‐methoxyergosta‐7,22‐dien‐3,5‐diol.     

New Cholinesterase‐Inhibiting Steroidal Alkaloids from Sarcococca saligna

Seven new steroidal alkaloids, 2‐hydroxysalignarine‐E (=(2′E,20S)‐20‐(dimethylamino)‐2β‐hydroxy‐3β‐(tigloylamino)pregn‐4‐ene; 1 ), 5,6‐dihydrosarconidine (=(20S)‐20‐(dimethylamino)‐3β‐(methylamino)‐5α‐pregn‐16‐ene; 2 ), salignamine (=(20S)‐20‐(methylamino)‐3β‐methoxypregna‐5,16‐diene; 3 ), 2‐hydroxysalignamine (=(20S)‐20‐(dimethylamino)‐2β‐hydroxy‐3β‐methoxypregna‐5,16‐diene; 4 ), salignarine‐F (=(2′E, 20S)‐20‐(dimethylamino)‐4β‐hydroxy‐3β‐(tigloylamino)pregn‐5‐ene; 5 ), salonine‐C (=(2′E,20S)‐20‐(dimethylamino)‐3β‐(tigloylamino)pregna‐4,14‐diene; 6 ), and N‐[formyl(methyl)amino]salonine‐B (=(20S)‐20‐[formyl(methyl)amino]‐3β‐methoxypregna‐5,16‐diene; 7 ) have been isolated from the MeOH extract of Sarcococca saligna, along with the six known alkaloids dictyophlebine ( 8 ), epipachysamine‐D ( 9 ), saracosine ( 10 ), iso‐N‐formylchonemorphine ( 11 ), sarcodinine ( 12 ), and alkaloid‐C ( 13 ). The structures of 1 – 7 were deduced from spectral data. Compounds 1 – 13 demonstrated significant activity against acetyl‐ and butyrylcholinesterase.