cas 4687-37-0, 3-(3,4-DIMETHOXY-PHENYL)-3-OXO-PROPIONIC ACID ETHYL ESTER

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Trifluoroethanol as a Unique Additive for the Chemoselective Electrooxidation of Enamines to Access Unsymmetrically Substituted NH-Pyrroles
An electrochemical method for the synthesis of unsymmetrically substituted NH-pyrroles is described. The synthetic strategy comprises a challenging heterocoupling between two structurally diverse enamines via sequential chemoselective oxidation, addition,
Baidya, Mrinmay,De Sarkar, Suman,Maiti, Debabrata,Roy, Lisa
supporting information

(2021/12/23)

Construction of isoxazolone-fused phenanthridinesviaRh-catalyzed cascade C-H activation/cyclization of 3-arylisoxazolones with cyclic 2-diazo-1,3-diketones
A Rh(iii)-catalyzed cascade C-H activation/intramolecular cyclization of 3-aryl-5-isoxazolones with cyclic 2-diazo-1,3-diketones was described, leading to the formation of isoxazolo[2,3-f]phenanthridine skeletons. The protocol features the simultaneous one-pot formation of two new C-C/C-N bonds and one heterocycle in moderate-to-good yields with good functional group compatibility. It is amenable to large-scale synthesis and further transformation.
Hu, Wangcheng,He, Xinwei,Zhou, Tongtong,Zuo, Youpeng,Zhang, Shiwen,Yang, Tingting,Shang, Yongjia
supporting information
p. 552 - 556
(2021/02/06)

Modular Tuning of Electrophilic Reactivity of Iridium Nitrenoids for the Intermolecular Selective α-Amidation of β-Keto Esters
We report herein an Ir-catalyzed intermolecular amino group transfer to β-keto esters (amides) to access α-aminocarbonyl products with excellent chemoselectivity. The key strategy was to engineer electrophilicity of the putative Ir-nitrenoids by tuning electronic property of the κ2-N,O chelating ligands, thus facilitating nucleophilic addition of enol π-bonds of 1,3-dicarbonyl substrates.
Lee, Minhan,Jung, Hoimin,Kim, Dongwook,Park, Jung-Woo,Chang, Sukbok
p. 11999 - 12004
(2020/08/06)

Compound for treating diabetes and/or related disorders
The invention discloses a compound for treating diabetes and/or related disorders, specifically a method for preventing, inhibiting and/or reversing amylin amyloid fibril formation, preventing isletsof Langerhans beta-cell death, preventing and/or reversing conversion of soluble human amylin to insoluble human amylin, and preventing and inhibiting and/or reversing cytotoxic amylin fibril formation. The invention also relates to a compound for preparing drugs for preventing and/or treating amylin amyloid-associated diseases.
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Paragraph 0324; 0325; 0326

(2020/05/14)

COMPOUNDS FOR TREATING DIABETES AND/OR RELATED CONDITIONS
Compounds useful for treating or preventing diabetes and related conditions, and for preventing, inhibiting or reversing amylin-amyloid fibril formation, preventing islets of Langerhans (Beta)-cell death, preventing or reversing the transition from soluble human amylin to insoluble human amylin, preventing and inhibiting or reversing cytotoxic amylin fibril formation. The invention relates to compounds of Formula (I) and compounds of Formula (II): (Formulae (I) and (II)).
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Paragraph 00151

(2020/05/21)

A orange flavone synthesis method (by machine translation)
The invention provides a method for synthesis of orange flavone, solve the existing orange flavone can only be from natural plant obtained by the separation, yield is relatively low, the problem of high cost. The invention first of all by the 3, 4 - dimet
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Paragraph 0037; 0046; 0055; 0064; 0073; 0082; 0091; 0100

(2019/03/08)

Rate Enhancement in CAN-Promoted Pd(PPh3)2Cl2-Catalyzed Oxidative Cyclization: Synthesis of 2-Ketofuran-4-carboxylate Esters
Stoichiometric ceric ammonium nitrate (CAN) and a catalytic amount of Pd(PPh3)2Cl2 (5 mol %) can rapidly produce multisubstituted 2-ketofuran-4-carboxylate esters from 2-propargylic 1,3-ketoesters via oxidative O-cyclization reaction. Pd(PPh3)2Cl2 was found to be the crucial catalyst as its inclusion greatly enhanced the rate of the reaction and cleanly afforded the products within minutes. Over 30 substrates were successfully converted to the desired compounds in mostly moderate to good yields.
Ruengsangtongkul, Sureeporn,Chaisan, Nattawadee,Thongsornkleeb, Charnsak,Tummatorn, Jumreang,Ruchirawat, Somsak
supporting information
p. 2514 - 2517
(2019/04/30)

Substituted phenyl pyrazolone derivatives and preparation and application (by machine translation)
The present invention provides a substituted phenyl pyrazolone derivatives, in particular to a 2 - phenyl - pyrazoline - 3 - ketone compound and its pharmaceutically acceptable salt, solvate. The substituted acetic acid ethyl ester with sodium hydroxide in aqueous solution in the [...] reflux reaction, then in the palladium-carbon and hydrogen under the action of the hydrogenolysis benzyl, phenyl [...] obtained, with the bromochlorodifluoromethane alkane reaction to obtain the chloro, finally with the secondary amine on the condensation to obtain the target compound. The invention substituted phenyl pyrazoline compounds in vitro exhibits excellent capability of eliminating the free radicals, and have more strongly inhibit H3 receptor activity, exhibits excellent penetration of the blood brain barrier capacity, has a unique dual active, therefore, its for cerebral apoplexy, Alzheimer's disease, Parkinson's disease, progressive neurodegenerative diseases such as frozen sickness treatment has a unique clinical effect. The compound of the invention for treating central system system related disease and inflammatory disease application of the medicament. The formula structure is as follows: (by machine translation)
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Paragraph 0034; 0039; 0040

(2019/01/08)

Investigate cleavage of β-O-4 linkage in lignin model compounds by aerobic oxidation of Cα and Cγ hydroxyl groups
The selective cleavage of common linkages in lignin polymers is a promising approach to generate valuable aromatic hydrocarbons. Herein, we found that on oxidation of Cα and Cγ hydroxyl groups in β-O-4 lignin model compounds with TEMPO catalyst resulted in the formation of 1,3-dicarbonyl TEMPO adduct. These oxidized products readily underwent fragmentation at Cα-Cβ bond in the presence of a catalytic amount of acid to generate corresponding carboxylic acid and phenol monomers.
Patil, Nikhil D.,Yan, Ning
supporting information
p. 3024 - 3028
(2016/07/06)

Selective cleavage of the Cα-Cβ linkage in lignin model compounds via Baeyer-Villiger oxidation
Lignin is an amorphous aromatic polymer derived from plants and is a potential source of fuels and bulk chemicals. Herein, we present a survey of reagents for selective stepwise oxidation of lignin model compounds. Specifically, we have targeted the oxidative cleavage of Cα-Cβ bonds as a means to depolymerize lignin and obtain useful aromatic compounds. In this work, we prepared several lignin model compounds that possess structures, characteristic reactivity, and linkages closely related to the parent lignin polymer. We observed that selective oxidation of benzylic hydroxyl groups, followed by Baeyer-Villiger oxidation of the resulting ketones, successfully cleaves the Cα-Cβ linkage in these model compounds. This journal is
Patil, Nikhil D.,Yao, Soledad G.,Meier, Mark S.,Mobley, Justin K.,Crocker, Mark
p. 3243 - 3254
(2015/03/18)

A one-pot copper(II)-catalyzed tandem synthesis of 2-substituted pyrrolo[1,2-b]pyridazin-4(1H)-ones
A one-pot copper(II)-catalyzed tandem synthesis of 2-substituted pyrrolo[1,2-b]pyridazin-4(1H)-ones from N-aminopyrroles was developed. This tandem reaction involves a Conrad-Limpach-type reaction, including the thermal condensation of N-aminopyrroles with the carbonyl group of β-oxo esters followed by the cyclization of Schiff base intermediates. Compared to the traditional Conrad-Limpach quinoline synthesis, we herein successfully applied copper(II) as a catalyst in this transformation to furnish 2-substituted pyrrolo[1,2-b]pyridazin-4(1H)-ones for the first time. Most of the substrates bearing electron-donating (EDG) and electron-withdrawing (EWG) groups worked well with this procedure. The corresponding products could be converted directly into diverse pyrrolo[1,2-b]pyridazine for drug discovery and materials science. A copper(II)-catalyzed tandem synthesis of 2-substituted pyrrolo[1,2-b]pyridazin-4(1H)-ones from N-aminopyrroles was developed, and the corresponding products could be converted directly into diverse pyrrolo[1,2-b]pyridazine for drug discovery and materials science.
Tan, Cun,Xiang, Haoyue,He, Qian,Yang, Chunhao
supporting information
p. 3656 - 3660
(2015/06/16)

Access to β-keto esters by palladium-catalyzed carbonylative coupling of aryl halides with monoester potassium malonates
New tricks for an old dog: The Pd-catalyzed carbonylative α-arylation of monoethyl potassium malonates with aryl bromides and reactive aryl chlorides provides a simple and direct route to aryl β-ketoesters. Because only stoichiometric amounts of carbon monoxide are employed, the method is ideal for the introduction of carbon isotopes into more complex structures. Copyright
Korsager, Signe,Nielsen, Dennis U.,Taaning, Rolf H.,Skrydstrup, Troels
supporting information
p. 9763 - 9766
(2013/09/23)

Design and synthesis of 6,7-methylenedioxy-4-substituted phenylquinolin-2(1H)-one derivatives as novel anticancer agents that induce apoptosis with cell cycle arrest at G2/M phase
Novel 6,7-methylenedioxy-4-substituted phenylquinolin-2(1H)-one derivatives 12a-n were designed and prepared through an intramolecular cyclization reaction and evaluated for in vitro anticancer activity. Among the synthesized compounds, 6,7-methylenedioxy-4-(2,4-dimethoxyphenyl)quinolin-2(1H)-one (12e) displayed potent cytotoxicity against several different tumor cell lines at a sub-micromolar level. Furthermore, results of fluorescence-activated cell sorting (FACS) analysis suggested that 12e induced cell cycle arrest in the G2/M phase accompanied by apoptosis in HL-60 and H460 cells. This action was confirmed by Hoechst staining and caspase-3 activation. Due to their easy synthesis and remarkable biological activities, 4-phenylquinolin-2(1H)-one analogs (4-PQs) are promising new anticancer leads based on the quinoline scaffold. Accordingly, compound 12e was identified as a new lead compound that merits further optimization and development as an anticancer candidate.
Chen, Yi-Fong,Lin, Yi-Chien,Huang, Po-Kai,Chan, Hsu-Chin,Kuo, Sheng-Chu,Lee, Kuo-Hsiung,Huang, Li-Jiau
p. 5064 - 5075
(2013/09/02)

Oxidative coupling reactions of 1,3-diarylpropene derivatives to dibenzo[a,c]cycloheptenes by PIFA
The oxidative cyclization reactions of a variety of α- benzylcinnamates can be selectively performed with hypervalent iodine as an oxidant. The dibenzo[a,c]cycloheptenes were isolated in up to 55 % yield. When an oxo substrate is applied, the yield was significantly increased. With this synthetic approach, a central intermediate for the synthesis of metasequirin-B was obtained in three steps from very simple starting materials. For this transformation, both aryl moieties have to be activated.
Hackeloeer, Kristina,Schnakenburg, Gregor,Waldvogel, Siegfried R.
scheme or table
p. 6314 - 6319
(2011/12/01)

Highly diastereoselective and enantioselective synthesis of α-hydroxy β-amino acid derivatives: Lewis base catalyzed hydrosilylation of α-acetoxy β-enamino esters
By design: A series of α-acetoxy-β-enamino esters 1 were synthesized and then subjected to catalytic asymmetric hydrosilylation. In the presence of a chiral Lewis base catalyst, the reactions proceeded smoothly to provide a wide range of chiral α-acetoxy β-amino acid derivatives in high yields with good diastereoselectivities and enantioselectivities. Copyright
Jiang, Yan,Chen, Xing,Zheng, Yongsheng,Xue, Zhouyang,Shu, Chang,Yuan, Weicheng,Zhang, Xiaomei
supporting information; experimental part
p. 7304 - 7307
(2011/09/16)

PHARMACEUTICAL COMPOSITION COMPRISING PYRAZOLONE DERIVATIVE
The present invention relates to pharmaceutical compositions containing a compound represented by formula (I), or a pharmaceutically acceptable prodrug or salt thereof, or a hydrate or solvate thereof as an active ingredient, (wherein, R1, R2, R3, and R4 are the same as R1, R2, R3, and R4 in the description of the present invention).
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Page/Page column 164-165

(2010/11/30)

Simple synthesis of eudesmin through oxidative coupling of carbanions and reductive catalytic hydrogenation of diketo diester
A simple synthesis of eudesmin (1) is described. The key fragments were diol 13, dicarbethoxyethane 4, and diketo diester 5, which were prepared via reductive catalytic hydrogenation and oxidative intermolecular coupling of carbanions. This method is useful to generate the core skeleton of an endo-endo furofuran ring. Copyright Taylor & Francis Group, LLC.
Jung, Jae-Chul,Park, Oee-Sook
p. 1665 - 1673
(2008/02/01)

Synthesis and herbicidal evaluation of novel 3-[(α-hydroxy- substituted)benzylidene]pyrrolidine-2,4-diones
A series of 3-[(α-hydroxy-substituted) benzylidene]pyrrolidine-2,4- dione derivatives were synthesized as candidate herbicides by reacting different aroyl acetates with N-substituted glycine esters. The new compounds were identified by 1H NMR spectroscopy and elemental analyses. Their herbicidal activities were evaluated. Some compounds exhibited excellent herbicidal activities at a dose of 187.5 g/ha. A suitable electron-donating substituent at the 2- and/or 4-position of the phenyl ring was essential for high herbicidal activity, a result that has not been reported before. It was also found that the title compound's structure-activity relationships were different from those of other similar kinds of earlier compounds, a result that may depend on the enol structure difference.
Zhu, Youquan,Zou, Xiaomao,Hu, Fangzhong,Yao, Changsheng,Liu, Bin,Yang, Huazheng
p. 9566 - 9570
(2007/10/03)

QUINAZOLINE DERIVATIVES
The invention relates to the use of compounds of the formula I: wherein: ring C is a 5-6 membered heterocyclic moiety; Z is -O-, -S-, or -CH2-; R1 is hydrogen, C1-4alkyl, C1-4alkoxymethyl, di(C1-4)alkoxy)methyl, C1-4alkanoyl, trifluoromethyl, cyano, amino, C2-5alkenyl, C2-5alkynyl, carboxy, C3-7cycloalkyl, C3-7-cycloalkylC1-3alkyl, or an optionally substituted group selected from phenyl, benzyl, phenylC2-4alkyl and a 5-6 membered heterocyclic group; n is an integer from 0 to 5; m is an integer from 0 to 3; R2 represents hydrogen, hydroxy, halgeno, cyano, nitro, trifluoromethyl, C1-3alkyl, C1-3alkoxy, C1-3alkylsulphanyl, -NR3R4 (wherein R3 and R4, which may be the same or different, each represents hydrogen or C1-3alkyl), or R5X1- (wherein X1 represents a direct bond, -CH2-, or a heteroatom linker group and R5 is an alkyl, alkenyl or alkynyl chain optionally substituted by for example hydroxy, amino, nitro, alkyl, cycloalkyl, alkoxyalkyl, or an optionally substituted group selected from pyridone, phenyl and a heterocyclic ring, which alkyl, alkenyl or alkynyl chain may have a heteroatom linker group, or R5 is an optionally substituted group selected from pyridone, phenyl and a heterocyclic ring, and salts thereof, in the manufacture of a medicament for use in the production of an antiangiogenic and/or vascular permeability reducing effect in warm-blooded animals, processes for the preparation of such compounds, pharmaceutical compositions containing a compound of formula I or a pharmaceutically acceptable salt thereof as active ingredient and compounds of formula I. The compounds of formula I and the pharmaceutically acceptable salts thereof inhibit the effects of VEGF, a property of value in the treatment of a number of disease states including cancer and rheumatoid arthritis.
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Page/Page column 32

(2010/02/11)

PHENYLPYRIMIDINE COMPOUND AND USE THEREOF
PROBLEM TO BE SOLVED: To provide a compound having excellent controlling effect on plant blight. SOLUTION: A plant blight controlling agent containing a phenylpyrimidine compound expressed by formula (1) has excellent controlling effect on plant blight. In the formula, R1 is hydrogen atom, a halogen atom or a 1-3C alkyl; R2 is hydrogen atom, a halogen atom or a 1-3C alkyl or R1 and R2 together form trimethylene group, tetramethylene group or CH=CH-CH=CH group; R3 is a 1-3C alkyl or a 3-4C alkynyl; and Z is Z1 or Z2.
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Page/Page column 19-20

(2008/06/13)

PYRAZOLOPYRIMIDINES AS CYCLIN DEPENDENT KINASE INHIBITORS
In its many embodiments, the present invention provides a novel class of pyrazolo[1,5-a]pyrimidine compounds as inhibitors of cyclin dependent kinases, methods of preparing such compounds, pharmaceutical compositions containing one or more such compounds, methods of preparing pharmaceutical formulations comprising one or more such compounds, and methods of treatment, prevention, inhibition, or amelioration of one or more diseases associated with the CDKs using such compounds or pharmaceutical compositions.
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Page/Page column 32

(2008/06/13)

PYRAZOLOPYRIMIDINES AS CYCLIN DEPENDENT KINASE INHIBITORS
In its many embodiments, the present invention provides a novel class of pyrazolo[1,5-a]pyrimidine compounds as inhibitors of cyclin dependent kinases, methods of preparing such compounds, pharmaceutical compositions containing one or more such compounds, methods of preparing pharmaceutical formulations comprising one or more such compounds, and methods of treatment, prevention, inhibition, or amelioration of one or more diseases associated with the CDKs using such compounds or pharmaceutical compositions.
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Page 31

(2008/06/13)

PYRAZOLOPYRIMIDINES AS CYCLIN DEPENDENT KINASE INHIBITORS
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Page 33

(2008/06/13)

PYRAZOLOPYRIMIDINES AS CYCLIN-DEPENDENT KINASE INHIBITORS
In its many embodiments, the present invention provides a novel class of pyrazolo[1,5-a]pyrimidine compounds as inhibitors of cyclin dependent kinases, methods of preparing such compounds, pharmaceutical compositions containing one or more such compounds, methods of preparing pharmaceutical formulations comprising one or more such compounds, and methods of treatment, prevention, inhibition, or amelioration of one or more diseases associated with the CDKs using such compounds or pharmaceutical compositions.
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Page 55

(2008/06/13)

4-Substituted 1,5-diarylpyrazole, analogues of celecoxib: Synthesis and preliminary evaluation of biological properties
A number of 5-aryl-1-[4-(methylsulfonyl)-phenyl]-1H-pyrazoles and 4-(5-aryl-1H-pyrazol-1-yl)benzenesulfonamides 3, 4, 5, 6, analogues of the COX-2 selective inhibitor celecoxib (celebrex), were synthesized. In order to verify the effects on the biological properties of certain substituents put on position 4 of the pyrazole nucleus, some of these compounds were screened in vivo for their anti-inflammatory and analgesic activities. Moreover, sodium salts of carboxylic acids 4 were tested in vitro for their platelet anti-aggregating properties. The results of these preliminary biological assays showed that new derivatives are not endowed with improved anti-inflammatory and analgesic properties, in comparison with celecoxib. In addition, docking studies were carried out on the most significative compounds to evaluate their interaction mode at the active site of both COX-1 and COX-2. Some remarks about the SAR of this class of COX-inhibitors are drown out.
Menozzi, Giulia,Merello, Luisa,Fossa, Paola,Mosti, Luisa,Piana, Antonietta,Mattioli, Francesca
p. 795 - 808
(2007/10/03)

Pyrrolidine-3-carboxylic acids as endothelin antagonists. 5. Highly selective, potent, and orally active ETA antagonists
The synthesis and structure-activity relationships (SAR) of a series of pyrrolidine-3-carboxylic acids as endothelin antagonists are described. The data shows an increase in selectivity when the methoxy of Atrasentan (ABT-627) is replaced with methyl, and the benzodioxole is replaced with dihydrobenzofuran. Adding a fluorine further increases the binding activity and provides a metabolically stable and orally bioavailable ETA-selective antagonist.
Jae,Winn,Von Geldern,Sorensen,Chiou,Nguyen,Marsh,Opgenorth
p. 3978 - 3984
(2007/10/03)

Simple and high yielding syntheses of β-keto esters catalysed by zeolites
Simple and high yielding syntheses of several β-keto esters, catalysed by zeolite Hβ are reported. The methods developed include condensation of aldehydes with ethyl diazoacetate and transesterification of β-keto esters with primary, secondary, allylic and benzylic alcohols etc., all catalysed by Hβ. It was further observed that under microwave irradiation the yields of many aromatic β-keto esters were enhanced appreciably.
Balaji,Chanda, Bhanu M.
p. 13237 - 13252
(2007/10/03)

An Expeditious Synthetic Route to Furolignans having Two Different Aryl Groups
3,4-Dimethyl-2-piperonyl-5-veratrylfuran has been synthesized starting from vanillin and piperonal by employing as the key steps cross-coupling of a bromo β-oxo ester and the sodium salt of another β-oxo ester, affording a 1,4-diketone, and selective reductive removal of an allylic hydroxy group by palladium oxide.
Anxin, Wu,Mingyi, Wang,Yonghong, Gan,Xinfu, Pan
p. 136 - 137
(2007/10/03)

Pyrrolidine-3-carboxylic acids as endothelin antagonists. 2. Sulfonamide-based ET(A)/ET(B) mixed antagonists
When the N,N-dialkylacetamide side chain of the highly ET(A)-selective endothelin antagonist ABT-627 (1; [2R,3R,4S]-2-(4-methoxyphenyl)-4-(1,3- benzodioxol-5-yl)-1-[[(N,N-dibutylamino)carbonyl]methyl]pyrrolidine-3- carboxylic acid; A-147627) is replaced by N,S-dialkylsulfonami-doethyl, the resultant analogs retain ET(A) affinity, but exhibit substantial ET(B) affinity as well. Structure-activity studies reveal that modifications in the length of the two alkyl groups, and in the substitution on the anisyl ring, are important in optimizing this 'balanced' antagonist profile. In particular the combination of an N-n-propyl group, an S-alkyl chain between four and six carbons in length, and a fluorine atom ortho to the aromatic OCH3 provides compounds with sub-nanomolar affinities for both receptor subtypes, and with ET(A)/ET(B) ratios close to 1. A number of these compounds also exhibit oral bioavailabilities (in rats) in the 30-50% range and have substantial plasma half-lives. The balanced receptor-binding profile of these potent and orally bioavailable compounds complements the ET(A) selectivity observed with 1.
Jae, Hwan-Soo,Winn, Martin,Dixon, Douglas B.,Marsh, Kennan C.,Nguyen, Bach,Opgenorth, Terry J.,Von Geldern, Thomas W.
p. 3217 - 3227
(2007/10/03)

Microbial synthesis of (+)-(3R)-ethyl 3-hydroxy-3-(3,4-dimethoxyphenyl)propionate
From the microbiological reduction of ethyl 3-oxo-3-(3,4-dimethoxyphenyl)-propionate, (+)-(3R)-ethyl 3-hydroxy-3-(3,4-dimethoxyphenyl)propionate was prepared on a quantitative scale. The absolute configuration was assigned by X-ray structural determination of the crystallized camphanate derivative.
Bardot, Valerie,Besse, Pascale,Gelas-Miahle, Yvonne,Remuson, Roland,Veschambre, Henri
p. 1077 - 1088
(2007/10/03)

(Phenylalkylaminoalkyloxy)-heteroaryl-compounds, processes and intermediates for their production and pharmaceutical compositions containing them
3-(Phenylalkylaminoalkylozy)-heteroaryl compounds having heart rate lowering and/or anti-ischemic effects, methods for their preparation and pharmaceutical compositions containing them are described. The compounds correspond to the general formula I STR1 or to the general formula XXXI STR2 in which the substituents have the meanings given the specification.
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(2008/06/13)

SYNTHESIS AND PHARMACOLOGICAL ACTIVITY OF 2-ARYL-3-ETHOXY-CARBONYL-5-HYDROXYBENZOFURANS
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Zotova, S. A.,Gololobova, T. M.,Stolyarchuk, A. A.,Stepanyuk, G. I.,Bobruk, V. P.,et al.
p. 26 - 30
(2007/10/02)

Synthesis and N.m.r. Spectra of 2,6- and 2,4-Diaryl-3,7-dioxabicyclooctanes
A series of isomeric 2,6- and 2,4-diaryl-3,7-dioxabicyclooctanes have been prepared via the corresponding threo, and erythro-dioxo-diesters.Comparison of their 1H and 13C n.m.r. spectra reveals small differences in chemical shifts and coupling constants which could be diagnostic in assigning structures to such compounds.The structure of 4-hydroxysesamin has been confirmed by direct correlation with sesamin.
Pelter, Andrew,Ward, Robert S.,Watson, Derrick J.,Jack, Ibiba R.
p. 183 - 190
(2007/10/02)

Phenanthroindolizidine and Related Alkaloids: Synthesis of Tylophorine, Septicine, and Deoxytylophorinine
Tylophorine (1) is synthesized in two ways.The first method begins with the synthesis of the amide-ester (7), which on reaction, successively, with triethyloxonium fluoroborate and sodium borohydride, gives the aminoester (8) selectively; hydrolysis and polyphosphoric acid-catalysed ring-closure of compound (9) gives the ketone (10) which yields tylophorine (1) on Clemmensen reduction.An alternative approach is by a biogenetically patterned sequence which involves condensation of (3,4-dimethoxybenzoyl)acetic acid (26) with 1-pyrroline (24) generated either in situ from putrescine by pea-seedling diamine oxidase or from ornithine by oxidation with N-bromosuccinimide; the product (16) condenses with 3,4-dimethoxyphenylacetaldehyde in benzene to give an enamine .This undergoes cyclisation and dehydration in methanol; sodium borohydride reduction then gives the alkaloid septicine (19) which, on oxidation with thallium(III) trifluoroacetate, yields tylophorine (1).Deoxytylophorinine (34) is made in an exactly analogous manner to the latter method for tylophorine.
Cragg, John E.,Herbert, Richard B.,Jackson, Frederick B.,Moody, Christopher J.,Nicolson, Ian T.
p. 2477 - 2486
(2007/10/02)

A New Synthesis of Septicine, a Secophenanthroindolizine Alkaloid
Septicine , an alkaloid isolated from Ficus septica and Tylophora asthmatica, has been synthesized using 2-(3',4'-dimethoxyphenacyl)pyrrolidine (6) and 3,4-dimethoxy-phenylacetyl chloride (11) as the essential intermediates.Condensation of 6 and 11 affords 2-(3',4'-dimethoxyphenacyl)-N-(3'',4''-dimethoxyphenylacetyl)pyrrolidine (12) which on treatment with potassium-t-butoxide furnishes 6,7-di-(3',4'-dimethoxyphenyl)-5-oxo-1,2,3,5,8,8a-hexahydroindolizine (13).LAH reduction of 13 affords septicine (1), identical (co-TLC, IR, PMR, m.m.p.) with a natural sample.
Mangla, V. K.,Bhakuni, D. S.
p. 748 - 749
(2007/10/02)