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Acta chemica Scandinavica. Series B: Organic chemistry and biochemistry最新文献

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Tobacco chemistry. 65. Two new 7,8-epoxycembranoids from tobacco. 烟草化学65.烟草中的两种新的 7,8-epoxycembranoids.
Acta chemica Scandinavica. Series B: Organic chemistry and biochemistry Pub Date : 1986-11-01 DOI: 10.3891/acta.chem.scand.40b-0855
I Wahlberg, A M Eklund, C Vogt, C R Enzell, J E Berg
{"title":"Tobacco chemistry. 65. Two new 7,8-epoxycembranoids from tobacco.","authors":"I Wahlberg, A M Eklund, C Vogt, C R Enzell, J E Berg","doi":"10.3891/acta.chem.scand.40b-0855","DOIUrl":"10.3891/acta.chem.scand.40b-0855","url":null,"abstract":"<p><p>Two new diterpenoids have been isolated from tobacco. They have been identified as the (1S,2E,4S,6R,7R,8R,11E)- and (1S,2E,4S,6R,7S,8S,11E)-7,8-epoxy-2,11-cembradiene-4,6-diols 1 and 2 by synthesis and X-ray analysis. The conformation about the 5,6 bond in some 7,8-epoxycembranoids is discussed, as is the biogenesis of the two new compounds.</p>","PeriodicalId":6886,"journal":{"name":"Acta chemica Scandinavica. Series B: Organic chemistry and biochemistry","volume":"40 10","pages":"855-60"},"PeriodicalIF":0.0,"publicationDate":"1986-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14687271","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 5
Tobacco smoke chemistry. 1. A chemical and mass spectrometric study of tobacco smoke alkyl 2-hydroxy-2-cyclopentenones. 烟草烟雾化学。1.烟草烟雾烷基 2-羟基-2-环戊烯酮的化学和质谱研究。
Acta chemica Scandinavica. Series B: Organic chemistry and biochemistry Pub Date : 1986-11-01 DOI: 10.3891/acta.chem.scand.40b-0839
J Arnarp, C Enzell, K Petersson, T Pettersson
{"title":"Tobacco smoke chemistry. 1. A chemical and mass spectrometric study of tobacco smoke alkyl 2-hydroxy-2-cyclopentenones.","authors":"J Arnarp, C Enzell, K Petersson, T Pettersson","doi":"10.3891/acta.chem.scand.40b-0839","DOIUrl":"10.3891/acta.chem.scand.40b-0839","url":null,"abstract":"<p><p>A series of alkyl 2-hydroxy-2-cyclopentenones, which comprise biologically and organoleptically active compounds, have been synthesized and subjected to high resolution mass spectrometric studies to clarify structurally significant fragmentation pathways. On the basis of these results, 26 alkyl 2-hydroxy-2-cyclopentenones were identified in the weakly acidic fraction of smoke condensate from American blend type cigarettes, eighteen of which had not been detected in tobacco smoke previously. The utility for identification purposes of the corresponding quinoxaline derivatives, obtained through condensation with o-phenylenediamine, is discussed.</p>","PeriodicalId":6886,"journal":{"name":"Acta chemica Scandinavica. Series B: Organic chemistry and biochemistry","volume":"40 10","pages":"839-54"},"PeriodicalIF":0.0,"publicationDate":"1986-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14687266","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 10
Reactions of pyrimidine nucleosides with aqueous alkalies: kinetics and mechanisms. 嘧啶核苷与水溶液的反应:动力学和机理。
Acta chemica Scandinavica. Series B: Organic chemistry and biochemistry Pub Date : 1986-11-01 DOI: 10.3891/acta.chem.scand.40b-0798
H Lönnberg, P Suokas, R Käppi, E Darzynkiewicz
{"title":"Reactions of pyrimidine nucleosides with aqueous alkalies: kinetics and mechanisms.","authors":"H Lönnberg,&nbsp;P Suokas,&nbsp;R Käppi,&nbsp;E Darzynkiewicz","doi":"10.3891/acta.chem.scand.40b-0798","DOIUrl":"https://doi.org/10.3891/acta.chem.scand.40b-0798","url":null,"abstract":"<p><p>Kinetics for the reactions of various cytosine and uracil nucleosides and their alkyl derivatives with aqueous sodium hydroxide have been studied by liquid chromatography. Blocking of the glycosyl hydroxyl groups with alkyl groups and changes in the glycon moiety configuration have been observed to exert only moderate effects on the rate of deamination of cytosine nucleosides. Methylation of the 4-amino group retards deamination considerably, while a methyl substituent at C5 is rate accelerating and at C6 only moderately rate retarding. These findings have been accounted for by a mechanism involving a rate limiting bimolecular displacement of the 4-amino group by a hydroxide ion. Analogous comparisons with uracil nucleosides suggest that the decomposition of uridine is initiated by an intermolecular attack of hydroxide ion on the C5 atom of the base moiety. In contrast, beta-D-arabino- and beta-D-lyxo-furanosyl derivatives appear to be cleaved via an intramolecular nucleophilic attack of the ionized 2'-hydroxyl group.</p>","PeriodicalId":6886,"journal":{"name":"Acta chemica Scandinavica. Series B: Organic chemistry and biochemistry","volume":"40 10","pages":"798-805"},"PeriodicalIF":0.0,"publicationDate":"1986-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14687261","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 7
Pyridyl groups for protection of the imide functions of uridine and guanosine. Exploration of their displacement reactions for site-specific modifications of uracil and guanine bases. 保护尿苷和鸟苷亚胺功能的吡啶基。尿嘧啶和鸟嘌呤碱基位点特异性修饰的置换反应探索。
Acta chemica Scandinavica. Series B: Organic chemistry and biochemistry Pub Date : 1986-11-01 DOI: 10.3891/acta.chem.scand.40b-0806
X X Zhou, C J Welch, J Chattopadhyaya
{"title":"Pyridyl groups for protection of the imide functions of uridine and guanosine. Exploration of their displacement reactions for site-specific modifications of uracil and guanine bases.","authors":"X X Zhou,&nbsp;C J Welch,&nbsp;J Chattopadhyaya","doi":"10.3891/acta.chem.scand.40b-0806","DOIUrl":"https://doi.org/10.3891/acta.chem.scand.40b-0806","url":null,"abstract":"<p><p>For the protection of the O-4 function of uridine and the O-6 of guanosine, 2-, 3- and 4-hydroxypyridines, 2-pyridinethiol, 6-methyl-2-hydroxy- and 6-methyl-3-hydroxypyridines have been employed. These substituted pyridines gave pyridyl-N-and/or pyridyl-O-substituted derivatives, depending both upon the position of the hydroxyl and methyl groups in the pyridine ring, at the C-4 and the C-6 of the uracil and guanine residues, respectively. These groups were found to be good leaving groups for nucleophilic substitution reactions by amines, thiolates and oximate. If needed, the rate of these substitution reactions could be conveniently increased by almost 1000-fold by conversion of the pyridyl moiety to its methiodide.</p>","PeriodicalId":6886,"journal":{"name":"Acta chemica Scandinavica. Series B: Organic chemistry and biochemistry","volume":"40 10","pages":"806-16"},"PeriodicalIF":0.0,"publicationDate":"1986-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14687263","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 16
Synthesis of trifluoromethylisoxazoloazines. 三氟甲基异恶唑嗪的合成。
Acta chemica Scandinavica. Series B: Organic chemistry and biochemistry Pub Date : 1986-10-01 DOI: 10.3891/acta.chem.scand.40b-0760
K Tanaka, E B Pedersen
{"title":"Synthesis of trifluoromethylisoxazoloazines.","authors":"K Tanaka,&nbsp;E B Pedersen","doi":"10.3891/acta.chem.scand.40b-0760","DOIUrl":"https://doi.org/10.3891/acta.chem.scand.40b-0760","url":null,"abstract":"<p><p>When reacted with mixtures of phosphorus pentoxide, aniline, and triethylamine hydrochloride, 5-acetamidoisoxazoles (2 and 3) gave isoxazolo[5,4-d]pyrimidines (4 and 7, respectively). The same reagent and cyclohexanone were used to prepare the isoxazoloquinoline 8.</p>","PeriodicalId":6886,"journal":{"name":"Acta chemica Scandinavica. Series B: Organic chemistry and biochemistry","volume":"40 9","pages":"760-3"},"PeriodicalIF":0.0,"publicationDate":"1986-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14941712","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 3
X-ray analysis of Ca2+ antagonists: 3,5-bis-(methoxycarbonyl)-2,6-dimethyl-4-(2-aminophenyl)-1,4- dihydropyridine hydrate. 钙离子拮抗剂的x射线分析:3,5-二-(甲氧羰基)-2,6-二甲基-4-(2-氨基苯基)-1,4-水合二氢吡啶。
Acta chemica Scandinavica. Series B: Organic chemistry and biochemistry Pub Date : 1986-10-01 DOI: 10.3891/acta.chem.scand.40b-0776
R Fossheim
{"title":"X-ray analysis of Ca2+ antagonists: 3,5-bis-(methoxycarbonyl)-2,6-dimethyl-4-(2-aminophenyl)-1,4- dihydropyridine hydrate.","authors":"R Fossheim","doi":"10.3891/acta.chem.scand.40b-0776","DOIUrl":"https://doi.org/10.3891/acta.chem.scand.40b-0776","url":null,"abstract":"","PeriodicalId":6886,"journal":{"name":"Acta chemica Scandinavica. Series B: Organic chemistry and biochemistry","volume":"40 9","pages":"776-8"},"PeriodicalIF":0.0,"publicationDate":"1986-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14941714","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 7
Reactions of 5-bromo substituted pyrimidine nucleosides with aqueous alkalies: kinetics and mechanisms. 5-溴取代嘧啶核苷与水溶液的反应:动力学和机理。
Acta chemica Scandinavica. Series B: Organic chemistry and biochemistry Pub Date : 1986-10-01 DOI: 10.3891/acta.chem.scand.40b-0768
R Käppi, H Lönnberg
{"title":"Reactions of 5-bromo substituted pyrimidine nucleosides with aqueous alkalies: kinetics and mechanisms.","authors":"R Käppi,&nbsp;H Lönnberg","doi":"10.3891/acta.chem.scand.40b-0768","DOIUrl":"https://doi.org/10.3891/acta.chem.scand.40b-0768","url":null,"abstract":"<p><p>Kinetics for the parallel and consecutive steps of the reactions of 5-bromocytidine, 5-bromouridine and its 5'-O-methyl and 2',3'-O-isopropylidene derivatives with aqueous alkalies were studied by LC. The mechanisms of the partial reactions involved are discussed.</p>","PeriodicalId":6886,"journal":{"name":"Acta chemica Scandinavica. Series B: Organic chemistry and biochemistry","volume":"40 9","pages":"768-75"},"PeriodicalIF":0.0,"publicationDate":"1986-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14941713","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 2
The cordycepin analogue of 2,5A and its threo isomer. Chemical synthesis, conformation and biological activity. 2,5a的虫草素类似物及其三聚体。化学合成、构象和生物活性。
Acta chemica Scandinavica. Series B: Organic chemistry and biochemistry Pub Date : 1986-09-01 DOI: 10.3891/acta.chem.scand.40b-0678
A Nyilas, L Vrang, A Drake, B Oberg, J Chattopadhyaya
{"title":"The cordycepin analogue of 2,5A and its threo isomer. Chemical synthesis, conformation and biological activity.","authors":"A Nyilas,&nbsp;L Vrang,&nbsp;A Drake,&nbsp;B Oberg,&nbsp;J Chattopadhyaya","doi":"10.3891/acta.chem.scand.40b-0678","DOIUrl":"https://doi.org/10.3891/acta.chem.scand.40b-0678","url":null,"abstract":"<p><p>A new synthesis of the cordycepin analogue of 2,5A and its threo isomer is reported along with an assessment of their conformations by circular dichroism spectroscopy. Evidence is also presented showing that these compounds are stable against 2,5A-specific phosphodiesterase and are not able to activate the 2,5A-dependent endoribonuclease, possibly due to a reduced binding to the latter enzyme as compared to that of 2,5A.</p>","PeriodicalId":6886,"journal":{"name":"Acta chemica Scandinavica. Series B: Organic chemistry and biochemistry","volume":"40 8","pages":"678-88"},"PeriodicalIF":0.0,"publicationDate":"1986-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14941710","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 15
Cation binding to parvalbumin studied by 113Cd and 23Na NMR. Peak assignment of rabbit (pI 5.5) parvalbumin. 用113Cd和23Na NMR研究了阳离子与小白蛋白的结合。兔(pI 5.5)小白蛋白的峰值分配。
Acta chemica Scandinavica. Series B: Organic chemistry and biochemistry Pub Date : 1986-09-01 DOI: 10.3891/acta.chem.scand.40b-0689
M Svärd, T Drakenberg
{"title":"Cation binding to parvalbumin studied by 113Cd and 23Na NMR. Peak assignment of rabbit (pI 5.5) parvalbumin.","authors":"M Svärd,&nbsp;T Drakenberg","doi":"10.3891/acta.chem.scand.40b-0689","DOIUrl":"https://doi.org/10.3891/acta.chem.scand.40b-0689","url":null,"abstract":"<p><p>Cation binding to three apoparvalbumins was studied by means of 113Cd NMR. The 3 parvalbumins that were investigated were carp pI 4.25, rabbit pI 5.5 and pike pI 5.0. The results showed that Cd2+ ions bind to the EF and CD sites of carp apoparvalbumin pI 4.25 with about the same affinity. For rabbit (pI 5.5) apoparvalbumin, Cd2+ binds preferentially to the EF site, while for pike (pI 5.0) apoparvalbumin, it was the CD site that exhibited somewhat higher affinity for Cd2+. The effect of Mn2+ on the 113Cd signals of rabbit parvalbumin was used to assign the 113Cd NMR signals to the EF and CD sites. The Mn2+ paramagnetic effect on rabbit and pike parvalbumins differed from that obtained for carp parvalbumin. This is in agreement with the assumption that the beta-lineage parvalbumins possess a third external site of higher affinity than the alpha-lineage parvalbumins. Furthermore, 23Na NMR was used to study Na+-Mg2+ competition in the native carp (pI 4.25) parvalbumin. The results showed that Na+ and Mg2+ compete for the same site, the third external site.</p>","PeriodicalId":6886,"journal":{"name":"Acta chemica Scandinavica. Series B: Organic chemistry and biochemistry","volume":"40 8","pages":"689-93"},"PeriodicalIF":0.0,"publicationDate":"1986-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14941711","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 5
High affinity protein-binding and enzyme-inducing activity of methyltrienolone in Pseudomonas testosteroni. 甲基三烯诺酮在睾酮假单胞菌中的高亲和力蛋白结合和酶诱导活性。
Acta chemica Scandinavica. Series B: Organic chemistry and biochemistry Pub Date : 1986-08-01 DOI: 10.3891/acta.chem.scand.40b-0515
A Pousette, K Carlström
{"title":"High affinity protein-binding and enzyme-inducing activity of methyltrienolone in Pseudomonas testosteroni.","authors":"A Pousette,&nbsp;K Carlström","doi":"10.3891/acta.chem.scand.40b-0515","DOIUrl":"https://doi.org/10.3891/acta.chem.scand.40b-0515","url":null,"abstract":"<p><p>The synthetic androgen methyltrienolone (R 1881) was shown to increase steroid delta 1 dehydrogenase activity when added to cultures of Pseudomonas testosteroni at concentrations of 10(-10)-10(-8)M. Incubation with a soluble extract of P. testosteroni showed that (3H)-R 1881 was bound to a macromolecule with high affinity (Kd 0.6 X 10(-9)M) and low capacity (number of binding sites 120 X 10(-15) mol/mg of protein). The (3H)-R 1881-macromolecule complex was partially destroyed following treatment with protease, was precipitated by addition of ammonium sulfate at 20% of saturation, sedimented at 6.3 S both in 0.01 and 0.4 M KCl solutions, and had an isoelectric point of pH 6.3. The complex was partially bound to DNA-cellulose. Analysis by sucrose gradient centrifugation indicated that neither (3H)-testosterone and (3H)-estradiol-17 beta nor (3H)-corticosterone were bound with high affinity to the (3H)-R 1881-binding macromolecule. It is suggested that the partially characterized R 1881-binding macromolecule, which at least in certain respects resembles androgen receptors described in mammalian cells, is involved in the inductive effect of R 1881 on the delta 1 dehydrogenase activity in P. testosteroni.</p>","PeriodicalId":6886,"journal":{"name":"Acta chemica Scandinavica. Series B: Organic chemistry and biochemistry","volume":"40 7","pages":"515-21"},"PeriodicalIF":0.0,"publicationDate":"1986-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14613858","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 4
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