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1.
2,3‐Bis[(p‐isothiocyanatomethylphenyl)methyl]‐6,7‐dihydro‐5H‐2a‐thia(2a‐SIV)‐2,3,4a,7a‐tetraaza‐cyclopent[cd]indene‐1,4(2H,3H)‐dithione ( 3 ), prepared by the reaction of 2,3‐dimethyl‐6,7‐dihydro‐5H‐2a‐thia(2a‐SIV)‐2,3,4a,7a‐tetraazacyclopent‐[cd]indene‐1,4(2H,3H)‐dithione ( 1 ) with p‐xylylene diisothio‐cyanate, reacted with N,N′‐dialkyl substituted diamines to give macrocyclic compounds bearing hypervalent sulfur by a ring closure reaction in good yields. These macrocyclic compounds were converted into ring‐expanded macrocyclic compounds with release of the hypervalent sulfur by treating with NaBH4 and CF3COOH.  相似文献   

2.
12π-Tetraazapentalenes, 2,3-disubstituted 6,7-dihydro-5H-2a-thia(2a-SIV)-2,3,4a,7a-tetraazacyclopent-[cd]indene-1,4(2H,3H)-dithiones, 1 and 7 , reacted with excess alkyl or aryl isothiocyanates and isocyanates to afford mono- and di-alkyl or aryl substituted tetraazapentalene derivatives which have the thiocarbonyl and carbonyl groups.  相似文献   

3.
Two new glycoluril derivatives, namely diethyl 6‐ethyl‐1,4‐dioxo‐1,2,2a,3,4,6,7,7b‐octahydro‐5H‐2,3,4a,6,7a‐pentaazacyclopenta[cd]indene‐2a,7b‐dicarboxylate, C14H21N5O6, (I), and 6‐ethyl‐2a,7b‐diphenyl‐1,2,2a,3,4,6,7,7b‐octahydro‐5H‐2,3,4a,6,7a‐pentaazacyclopenta[cd]indene‐1,4‐dione, C20H21N5O2, (II), both bearing two free syn‐urea NH groups and two ureidyl C=O groups, assemble the same one‐dimensional chains in the solid state running parallel to the [010] direction via N—H...O hydrogen bonds. Furthermore, the chains of (I) are linked together into two‐dimensional networks via C—H...O hydrogen bonds.  相似文献   

4.
On Rearrangements by Cyclialkylations of Arylpentanols to 2,3‐Dihydro‐1 H ‐indene Derivatives. Part 4. The Acid‐Catalyzed Cyclialkylation of 2,4‐Dimethyl‐2‐phenyl[3‐ 13 C]pentan‐3‐ol The cyclialkylation of 2,4‐dimethyl‐2‐phenyl[3‐13C]pentan‐3‐ol ( 4 ) gives only 2,3‐dihydro‐1,1,2,3‐tetramethyl‐1H‐[3‐13C]indene ( 6 ) (cf. Scheme 2) and not a trace of the isotopomeric 2,3‐dihydro‐1,1,2,3‐tetramethyl‐1H‐[2‐13C]indene ( 5 ). The mechanism proposed in [3] for the cyclialkylation of 4 (cf. Scheme 2, Path A) has, therefore, to be abandoned. The mechanism of Scheme 2, Path B, is proposed and may be considered as definitively established.  相似文献   

5.
A series of 2‐substituted 2H‐thieno[3,4‐e][1,2,4]thiadiazin‐3(4H)‐one 1,1‐dioxides ( 2 ), 2‐substituted 2H‐thieno[2,3‐e][1,2,4]thiadiazin‐3(4H)‐one 1,1‐dioxides ( 3 ), 2‐substituted 4,6‐dihydropyrazolo[4,3‐e]‐[1,2,4]thiadiazin‐3(2H)‐one 1,1‐dioxides ( 4 ), 2‐substituted 2,3‐dihydrooxazolo[3,2‐b]thieno[3,4‐e]‐[1,2,4]thiadiazine 5,5‐dioxides, ( 5 ), 6‐substituted 6,7‐dihydro‐2H‐oxazolo[3,2‐b]pyrazolo[4,3‐e][1,2,4]thia‐diazine 9,9‐dioxides ( 6 ) and 7‐substituted 6,7‐dihydro‐2H‐oxazolo[3,2‐b]pyrazolo[4,3‐e][1,2,4]thiadiazine 9,9‐dioxides ( 7 ) were synthesized as potential psychotropic agents.  相似文献   

6.
On Rearrangements by Cyclialkylations of Arylpentanols to 2,3‐Dihydro‐1 H ‐indene Derivatives. Part 3. The Acid‐Catalyzed Cyclialkylation of 3,4‐Dimethyl‐ and 3‐([ 2 H 3 ]Methyl)‐4‐methyl‐3‐phenylpentan‐2‐ol The cyclialkylation of 2‐([2H3]methyl)‐4‐methyl‐4‐phenyl[1,1,1‐2H3]pentan‐3‐ol ( 4 ) yielded a 1 : 1 mixture of 1,1‐di([2H3]methyl)‐2,3‐dimethyl‐1H‐indene ( 5 ) and of 2,3‐dihydro‐2,3‐di([2H3]methyl)‐1,1‐dimethyl‐1H‐indene ( 6 ) (Scheme 1) [1]. However, it was not clear whether the transposition takes place through the successive migration of a Ph, a Me and again the Ph group (Scheme 2, Path A: shift IV → VII → VIIa ) or through Ph‐, Me‐, and then i‐Pr‐group (Scheme 2, Path B: IV → VII → VIIb ). The cyclialkylation of 3‐([2H3]methyl)‐4‐methyl‐3‐phenylpentan‐2‐ol ( 7 ) yielded only one product, the 2,3‐dihydro‐2‐([2H3]methyl)‐1,1,3‐trimethyl‐1H‐indene ( 8 ), in accordance with the migrations according to Path A. This result is also a support for the total mechanism proposed for the cyclialkylation of 4 (Scheme 2). The transition of a tertiary to a secondary carbenium ion is not definitely ensured (see [1]).  相似文献   

7.
On Rearrangements by Cyclialkylations of Arylpentanols to 2,3‐Dihydro‐1 H ‐indene Derivatives. Part 2. An Unexpected Rearrangement by the Acid‐Catalyzed Cyclialkylation of 2,4‐Dimethyl‐2‐phenylpentan‐3‐ol under Formation of trans ‐2,3‐Dihydro‐1,1,2,3‐tetramethyl‐1 H ‐indene The acid catalyzed‐cyclialkylation of 4‐(2‐chloro‐phenyl)‐2,4‐dimethylpentan‐2‐ol ( 1 ) gave two products: 4‐chloro‐2,3‐dihydro‐1,1,3,3‐tetramethyl‐1H‐indene ( 2 ) and also trans‐4‐chloro‐2,3‐dihydro‐1,1,2,3‐tetramethyl‐1H‐indene ( 3 ). A mechanism was proposed in Part 1 (cf. Scheme 1) for this unexpected rearrangement. This mechanism would mainly be supported by the result of the cyclialkylation of 2,4‐dimethyl‐2‐phenylpentan‐3‐ol ( 4 ), which, with respect to the similarity of ion II in Scheme 1 and ion V in Scheme 2, should give only product 5 . This was indeed the experimental result of this cyclialkylation. But the result of the cyclialkylation of 1,1,1,2′,2′,2′‐hexadeuterated isomer [2H6]‐ 4 of 4 (cf. Scheme 3) requires a different mechanism as for the cyclialkylation of 1 . Such a mechanism is proposed in Schemes 5 and 6. It gives a satisfactory explanation of the experimental results and is supported by the result of the cyclialkylation of 2,4‐dimethyl‐3‐phenylpentan‐3‐ol ( 9 ; Scheme 7). The alternative migration of a Ph or of an i‐Pr group (cf. Scheme 6) is under further investigation.  相似文献   

8.
Reported here are the single‐crystal X‐ray structure analyses of bis‐μ‐methanol‐κ4O:O‐bis{[hydrotris(3‐phenyl‐2‐sulfanylidene‐2,3‐dihydro‐1H‐1,3‐imidazol‐1‐yl)borato‐κ3H,S,S′](methanol‐κO)sodium(I)}, [Na2(C27H22BN6S3)2(CH4O)4] (NaTmPh), bis‐μ‐methanol‐κ4O:O‐bis{[hydrotris(3‐isopropyl‐2‐sulfanylidene‐2,3‐dihydro‐1H‐1,3‐imidazol‐1‐yl)borato‐κ3H,S,S′](methanol‐κO)sodium(I)}–diethyl ether–methanol (1/0.3333/0.0833), [Na2(C18H28BN6S3)2(CH4O)4]·0.3333C4H10O·0.0833CH3OH (NaTmiPr), and a novel anhydrous form of sodium hydrotris(methylthioimidazolyl)borate, poly[[μ‐hydrotris(3‐methyl‐2‐sulfanylidene‐2,3‐dihydro‐1H‐1,3‐imidazol‐1‐yl)borato]sodium(I)], [Na(C12H16BN6S3)] ([NaTmMe]n). NaTmiPr and NaTmPh have similar dimeric molecular structures with κ3H,S,S′‐bonding, but they differ in that NaTmPh is crystallographically centrosymmetric (Z′ = 0.5) while NaTmiPr contains one crystallographically centrosymmetric dimer and one dimer positioned on a general position (Z′ = 1.5). [NaTmMe]n is a one‐dimensional coordination polymer that extends along the a direction and which contains a hitherto unseen side‐on η2‐C=S‐to‐Na bond type. An overview of the structural preferences of alkali metal soft scorpionate complexes is presented. This analysis suggests that these thione‐based ligands will continue to be a rich source of interesting alkali metal motifs worthy of isolation and characterization.  相似文献   

9.
The crystal structures of 1,2‐dihydro‐1,1′‐bi[thiazolo[3,2‐a]quinoline]‐10a,10a′‐diium diiodide hemihydrate, C22H16N2S22+·2I·0.5H2O, and 1,2‐dihydro‐1,1′‐bi[thiazolo[3,2‐a]quinoline]‐10a,10a′‐diium iodide triiodide, C22H16N2S22+·I·I3, obtained during the reaction of 1,4‐bis(quinolin‐2‐ylsulfanyl)but‐2‐yne (2TQB) with iodine, have been determined at 120 K. The crystalline products contain the dication as a result of the reaction proceeding along the iodocyclization pathway. This is fundamentally different from the previously observed reaction of 1,4‐bis(quinolin‐8‐ylsulfanyl)but‐2‐yne (8TQB) with iodine under similar conditions. A comparative analysis of the possible conformational states indicates differences in the relative stabilities and free rotation for the 2‐ and 8‐thioquinoline derivatives which lead to a disparity in the convergence of the potential reaction centres for 2TQB and 8TQB.  相似文献   

10.
Two new iridoids, methyl (+)‐rel‐(1R,3S,4R,5R,8R,9R)‐1,3,4,5,8,9‐hexahydro‐8‐hydroxy‐3‐methoxy‐2H‐1a,2‐dioxacyclopent[cd]indene‐4‐carboxylate ( 1 ) and methyl (+)‐rel‐(1R,3S,4S,5R,8R,9R)‐1,3,4,5,8,9‐hexahydro‐8‐hydroxy‐3‐methoxy‐2H‐1a,2‐dioxacyclopent[cd]indene‐4‐carboxylate ( 2 ), were isolated from Viburnum cylindricum along with 14 known compounds. Their structures were determined by spectroscopic analyses. This type of iridoids bearing a MeO group at C(3) was discovered for the first time.  相似文献   

11.
The cycloadditions of methyl diazoacetate to 2,3‐bis(trifluoromethyl)fumaronitrile ((E)‐ BTE ) and 2,3‐bis(trifluoromethyl)maleonitrile ((Z)‐ BTE ) furnish the 4,5‐dihydro‐1H‐pyrazoles 13 . The retention of dipolarophile configuration proceeds for (E)‐ BTE with > 99.93% and for (Z)‐ BTE with > 99.8% (CDCl3, 25°), suggesting concertedness. Base catalysis (1,4‐diazabicyclo[2.2.2]octane (DABCO), proton sponge) converts the cycloadducts, trans‐ 13 and cis‐ 13 , to a 94 : 6 equilibrium mixture (CDCl3, r.t.); the first step is N‐deprotonation, since reaction with methyl fluorosulfonate affords the 4,5‐dihydro‐1‐methyl‐1H‐pyrazoles. Competing with the cis/trans isomerization of 13 is the formation of a bis(dehydrofluoro) dimer (two diastereoisomers), the structure of which was elucidated by IR, 19F‐NMR, and 13C‐NMR spectroscopy. The reaction slows when DABCO is bound by HF, but F? as base keeps the conversion to 22 going and binds HF. The diazo group in 22 suggests a common intermediate for cis/trans isomerization of 13 and conversion to 22 : reversible ring opening of N‐deprotonated 13 provides 18 , a derivative of methyl diazoacetate with a carbanionic substituent. Mechanistic comparison with the reaction of diazomethane and dimethyl 2,3‐dicyanofumarate, a related tetra‐acceptor‐ethylene, brings to light unanticipated divergencies.  相似文献   

12.
On Rearrangements by Cyclialkylations of Arylpentanols to 2,3‐Dihydro‐1 H ‐indene Derivatives. Part 1. An Unexpected Rearrangement by the Acid‐Catalyzed Cyclialkylation of 4‐(2‐Chlorophenyl)‐2,4‐dimethyl pentan‐2‐ol under Formation of trans ‐4‐Chloro‐2,3‐dihydro‐1,1,2,3‐tetramethyl‐1 H ‐indene The acid‐catalyzed cyclialkylation of 2,4‐dimethyl‐4‐phenylpentan‐2‐ol led exclusively to the expected product, 2,3‐dihydro‐1,1,3,3‐tetramethyl‐1H‐indene. However, analogous cyclialkylation of 4‐(2‐chlorophenyl)‐2,4‐dimethylpentan‐2‐ol ( 1 ) gave a ca. 1 : 1 mixture of 4‐chloro‐2,3‐dihydro‐1,1,3,3‐tetramethyl‐1H‐indene ( 2 ) and of trans‐4‐chloro‐2,3‐dihydro‐1,1,2,3‐tetramethyl‐1H‐indene ( 3 ; Scheme 1). The specific action of the Cl substituent is investigated and a mechanism for this unexpected frame‐work transposition proposed.  相似文献   

13.
The oxoisoaporphines 2,3‐dihydro‐7H‐dibenzo[de,h]quinolin‐7‐one, 2,3‐dihydro‐5‐methoxy‐7H‐dibenzo [de,h] quinolin‐7‐one, 5‐methoxy‐6‐hydroxy‐2,3‐dihydro‐7H‐dibenzo[de,h]quinolin‐7‐one, 5,6‐dimethoxy‐2,3‐dihydro‐7H‐dibenzo[de,h]quinolin‐7‐one and 5,6‐methylenedi‐oxy‐2,3‐dihydro‐7H‐dibenzo[de,h]quinolin‐7‐one were prepared by cyclization of phenylethylaminophthalides with polyphosphoric acid or by treating 1‐(2‐carboxyphenyl)‐3,4‐dihydroisoquinoline hydrochloride with sulfuric acid at 0 °C. The structures were confirmed and 1H and 13C NMR spectra were completely assigned using a combination of one‐ and two‐dimensional NMR techniques. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   

14.
By reaction with sodium ethoxide and as a function of their structures, 2‐[(1‐alkyl(aryl)‐4‐cyano‐6,7‐dihydro‐5H‐cyclopenta[c ]pyridin‐3‐yl)oxy]acetamides 11 gave 1‐amino‐5‐alkyl(aryl)‐7,8‐dihydro‐6H‐cyclopenta[d ]furo[2,3‐b ]pyridine‐2‐carboxamides 10 and/or 1‐alkyl(aryl)‐3‐amino‐6,7‐dihydro‐5H‐cyclopenta[c ]pyridine‐4‐carbonitriles 12 .  相似文献   

15.
3‐Alkyl/aryl‐3‐ureido‐1H,3H‐quinoline‐2,4‐diones ( 2 ) and 3a‐alkyl/aryl‐9b‐hydroxy‐3,3a,5,9b‐tetrahydro‐1H‐imidazo[4,5‐c]quinoline‐2,4‐diones ( 3 ) react in boiling concentrated HCl to give 5‐alkyl/aryl‐4‐(2‐aminophenyl)‐1,3‐dihydro‐2H‐imidazol‐2‐ones ( 6 ). The same compounds were prepared by the same procedure from 2‐alkyl/aryl‐3‐ureido‐1H‐indoles ( 4 ), which were obtained from the reaction of 3‐alkyl/aryl‐3‐aminoquinoline‐2,4(1H,3H)‐diones ( 1 ) with 1,3‐diphenylurea or by the transformation of 3a‐alkyl/aryl‐9b‐hydroxy‐3,3a,5,9b‐tetrahydro‐1H‐imidazo[4,5‐c]quinoline‐2,4‐diones ( 3 ) and 5‐alkyl/aryl‐4‐(2‐aminophenyl)‐1,3‐dihydro‐2H‐imidazol‐2‐ones ( 6 ) in boiling AcOH. The latter were converted into 1,3‐bis[2‐(2‐oxo‐2,3‐dihydro‐1H‐imidazol‐4‐yl)phenyl]ureas ( 5 ) by treatment with triphosgene. All compounds were characterized by 1H‐ and 13C‐NMR and IR spectroscopy, as well as atmospheric pressure chemical‐ionisation mass spectra.  相似文献   

16.
Three new diterpenoids, together with three known ones, were isolated from the air‐dried whole herbs of Rabdosia lophanthoides var. gerardiana. The structures of the new diterpenoids were established as 3,4‐dihydro‐11‐hydroxy‐10‐(1‐hydroxy‐1‐methylethyl)‐2,2,6‐trimethylnaphtho[1,8‐bc]oxocin‐5(2H)‐one ( 1 ), 11,12,15‐trihydroxyabieta‐5,8,11,13‐tetraen‐7‐one ( 2 ), (2R,3S,4S,4aR,8S,9aS,13aS,16aS)‐3,4,4a,8,9,9a,10,11,12,13,14,16a‐dodecahydro‐2‐(hydroxymethyl)‐6,6,10,10‐tetramethyl‐2H‐benzo[4,5]cyclohepta[1,2‐h]pyrano[2,3‐b][1,4]benzodioxepine‐3,4,8,13a,15(6H)‐pentol ( 3 ) by spectroscopic methods, including extensive 1D‐ and 2D‐NMR analyses. The structures of the known compounds were identified by comparison of their physical and spectroscopic data with those reported in the literature.  相似文献   

17.
Water hyacinth (Eichhornia crassipes) is a cause of great concern in terms of environmental and agricultural impacts in many parts of the world. Phytochemical investigation of water hyacinth led to the isolation of six new phenylphenalenes, 2,3‐dihydro‐3,9‐dihydroxy‐5‐methoxy‐4‐phenyl‐1H‐phenalen‐1‐one ( 1 ), 2,3‐dihydro‐8‐methoxy‐9‐phenyl‐1H‐phenalene‐1,4‐diol ( 2 ), 2,3‐dihydro‐4,8‐dimethoxy‐9‐phenyl‐1H‐phenalen‐1‐ol ( 3 ), 2,3‐dihydro‐9‐(4‐hydroxyphenyl)‐8‐methoxy‐1H‐phenalene‐1,4‐diol ( 4 ), 2,6‐dimethoxy‐9‐phenyl‐1H‐phenalen‐1‐one ( 5 ), and 7‐(4‐hydroxyphenyl)‐5,6‐dimethoxy‐1H‐phenalen‐1‐one ( 6 ), together with the four known compounds 7 – 10 . Their structures were elucidated by spectrometric methods including 1D‐ and 2D‐NMR, and MS analysis. These compounds may be involved in allelopathic interactions of water hyacinth with neighboring plants.  相似文献   

18.
This paper presents the synthesis of a series of 5,6‐dihydro‐4H,8H‐pyrimido[1,2,3‐cd]purine‐8,10(9H)‐dione ring system derivatives with a [1,2,3]triazole ring bonded in position 2. The procedure is based on cycloaddition of substituted alkyl azides to the terminal triple bond of 5,6‐dihydro‐2‐ethynyl‐9‐methyl‐4H,8H‐pyrimido[1,2,3‐cd]purine‐8,10(9H)‐dione ( 4 ). This cycloaddition produced two regioisomers ?5,6‐dihydro‐9‐methyl‐2‐(1‐substituted‐1H‐[1,2,3]triazol‐5‐yl)‐4H,8H‐pyrimido[1,2,3‐cd]purine‐8,10(9H)‐dione ( 7 ) and 2‐(1‐substituted‐1H‐[1,2,3]triazol‐4‐yl) derivative 8 . The required 2‐ethynyl deriva tive 4 was obtained from the starting 2‐unsubstituted compound 1 by bromination to yield the 2‐bromo derivative 2 , which was converted by Sonogashira reaction to trimethylsilylethyne 3 and finally, the protective trimethylsilyl group was removed by hydrolysis.  相似文献   

19.
Diethyl azodicarboxylate and 3,4,5,6‐tetrachloro‐1,2‐benzoquinone react with cyclopentano‐ and cycloheptano‐fused thienopyrimidines to form the oxidative dimer of the starting material via S—S bond formation. Reaction of two equivalents of 2,2′‐(cyclohexa‐2′,5′‐diene‐1,4‐diylidene)dimalononitrile with thienopyrimidines afforded 3‐(4′,4′‐dicyanomethylene‐cycloalka[a]‐2,5‐dienyl)‐4‐oxo‐6,7,8,9‐tetrahydro‐5H‐cyclo‐hepta[4,5]‐[1,3]thiazolo[3,2‐a]‐thieno[2,3‐d]pyrimidin‐2‐ylidene‐2‐dicarbonitriles. The thioenopyrimidines react with 2‐[1,3‐dioxo‐1H‐inden‐2(3H)‐ylidene]malononitrile to produce 1,3,5′‐trioxo‐1,3,3′,5′‐tetrahydrospiro‐(indene‐2,2′‐thiazolo[2,3‐b]‐cycloalkyl[b]‐thieno[2,3‐d]pyrimidine)‐3′‐carbonitriles. However, the reaction of thienopyrimidines with 2,3‐dicyano‐1,4‐naphthoquinone proceeded to afford the fused cycloalkyl‐thieno form of naphtho[1,3]thiazolo[3,2‐a]thieno[2,3‐d]pyrimidine‐6.7,12‐triones. Reaction of 2‐hydrazino‐5,6,7,8‐tetrahydrobenzo[b]thieno[2,3‐d]pyrimidine‐4(1H)‐one with dimethyl acetylenedicarboxylate and ethyl propiolate, respectively, afforded cyclohexano‐fused (Z)‐dimethyl 2[(E)‐4‐oxo‐3,4‐dihydrothieno[2,3‐d]pyrimidine‐2(1H)‐ylidene)hydrazono]succinate and thieno‐pyrimidinotriazine. Both oxidative dimers of thienopyrimidines showed high inhibition of Hep‐G2 cell growth compared with the growth of untreated control cells. Moreover, the cycloheptano‐fused thiazinothienopyrimidine indicates a promising specific antitumor agent against Hep‐G2 cells because its IC50 is < 20 μM.  相似文献   

20.
The chemical synthesis of deuterated isomeric 6,7‐dihydroxydodecanoic acid methyl esters 1 and the subsequent metabolism of esters 1 and the corresponding acids 1a in liquid cultures of the yeast Saccharomyces cerevisiae was investigated. Incubation experiments with (6R,7R)‐ or (6S,7S)‐6,7‐dihydroxy(6,7‐2H2)dodecanoic acid methyl ester ((6R,7R)‐ or (6S,7S)‐(6,7‐2H2)‐ 1 , resp.) and (±)‐threo‐ or (±)‐erythro‐6,7‐dihydroxy(6,7‐2H2)dodecanoic acid ((±)‐threo‐ or (±)‐erythro‐(6,7‐2H2)‐ 1a , resp.) elucidated their metabolic pathway in yeast (Tables 1–3). The main products were isomeric 2H‐labeled 5‐hydroxydecano‐4‐lactones 2 . The absolute configuration of the four isomeric lactones 2 was assigned by chemical synthesis via Sharpless asymmetric dihydroxylation and chiral gas chromatography (Lipodex ® E). The enantiomers of threo‐ 2 were separated without derivatization on Lipodex ® E; in contrast, the enantiomers of erythro‐ 2 could be separated only after transformation to their 5‐O‐(trifluoroacetyl) derivatives. Biotransformation of the methyl ester (6R,7R)‐(6,7‐2H2)‐ 1 led to (4R,5R)‐ and (4S,5R)‐(2,5‐2H2)‐ 2 (ratio ca. 4 : 1; Table 2). Estimation of the label content and position of (4S,5R)‐(2,5‐2H2)‐ 2 showed 95% label at C(5), 68% label at C(2), and no 2H at C(4) (Table 2). Therefore, oxidation and subsequent reduction with inversion at C(4) of 4,5‐dihydroxydecanoic acid and transfer of 2H from C(4) to C(2) is postulated. The 5‐hydroxydecano‐4‐lactones 2 are of biochemical importance: during the fermentation of Streptomyces griseus, (4S,5R)‐ 2 , known as L‐factor, occurs temporarily before the antibiotic production, and (?)‐muricatacin (=(4R,5R)‐5‐hydroxy‐heptadecano‐4‐lactone), a homologue of (4R,5R)‐ 2 , is an anticancer agent.  相似文献   

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