Wittig type reactions of 2-formylated derivatives of 6-methylergoline - I

1982 ◽  
Vol 47 (6) ◽  
pp. 1636-1640 ◽  
Author(s):  
Jan Beneš ◽  
Jiří Holubek
Keyword(s):  
Wittig Reaction ◽  
Sodium Hydride ◽  
Ethyl Esters ◽  
Acrylic Acids ◽  
Derivatives Of

Using the Horner-Wittig reaction, aldehydes I and II were converted, with high E-selectivity, into ethyl esters of substituted acrylic acids, VI and VII. The N-anions generated by deprotonation of derivative I-V with sodium hydride in tetrahydrofuran reacted with vinyltriphenylphosphonium bromide with the formation of derivatives of pyrrolo[1,2-a]ergoline-I, XI-XV.

1-Substitution derivatives of 4-aryl-2,3-dibromo-1-naphthol

1981 ◽  
Vol 46 (9) ◽  
pp. 2116-2122 ◽  
Author(s):  
Jiří Křepelka ◽  
Jiří Roubík ◽  
Jiří Holubek
Keyword(s):  
Aqueous Medium ◽  
Ethyl Esters ◽  
Derivatives Of

Alkylation of 7-ethyl-4-(4-ethylphenyl)-2,3-dibromo-1-naphthol (I) with ethyl esters of ω-bromoalkanoic acids XX-XXIII in a non-aqueous medium gave the 1-substitution derivatives II, IV, VI and VIII which were hydrolyzed to the acids III, V, VII and IX. The acid III was used for syntheses of the esters X-XIII and amides XIV-XVIII. Compounds II-XVIII exhibited moderate antineoplastic effects in animals with transplanted tumours; best results were observed with the compound II.

Synthesis and Biological Effects of N-(2-Phosphonomethoxyethyl) Derivatives of Deazapurine Bases

1993 ◽  
Vol 58 (6) ◽  
pp. 1419-1429 ◽  
Author(s):  
Hana Dvořáková ◽  
Antonín Holý
Keyword(s):  
Biological Effects ◽  
Sodium Hydride ◽  
Cesium Carbonate ◽  
Cytostatic Effect ◽  
Phosphonic Acids ◽  
Dna Viruses ◽  
Purine Bases ◽  
Heterocyclic Bases ◽  
L 1210 Leukemia ◽  
Derivatives Of

Analogs of antiviral 9-(2-phosphonomethoxyethyl)adenine (PMEA,II), containing modified purine bases 1-deazaadenine (VII, 3-deazapurine (XI), 7-deaza-7-cyanoadenine (XIIIb) and 3-deazaguanine (XXIb) were prepared by alkylation of the heterocyclic bases with bis(2-propyl) 2-chloroethoxymethylphosphonate (V) in dimethylformamide in the presence of sodium hydride or cesium carbonate. The obtained protected derivatives were deblocked with bromotrimethylsilane to give the phosphonic acids. 3-DeazaPMEG (XXIb) is active against DNA viruses and exhibits a marked cytostatic effect against L-1210 leukemia.

CERTAIN REACTIONS OF GAMMA KETONIC ACIDS

1934 ◽  
Vol 11 (3) ◽  
pp. 382-394 ◽  
Author(s):  
C. F. H. Allen ◽  
J. B. Normington ◽  
C. V. Wilson
Keyword(s):  
Levulinic Acid ◽  
Grignard Reagent ◽  
Acetyl Chloride ◽  
Methyl Esters ◽  
Open Chain ◽  
Unsaturated Lactones ◽  
Acrylic Acids ◽  
Derivatives Of

A considerable number of highly substituted acrylic acids or their lactols have been synthesized, and the Grignard reagent used to differentiate between the two possible structures. Acetyl chloride was found to be a satisfactory confirmatory agent, giving chlorides with the lactols, but not reacting with the open-chain acids. From the available evidence it is concluded that the differences may be attributed to cis-trans isomerism.Two other series of ketonic acids were investigated with both reagents; the Grignard reagent indicated mostly open-chain structures. The use of acetyl chloride led to a variety of products; by varying the procedure, dimers of undetermined structure, unsaturated lactones, enolic acetates, and methyl esters were obtained.Cyclohexanone gave cyclohexenyl acetate with acetyl chloride.The mechanism of the reactions is discussed, as well as the evidence for the possible structures of derivatives of levulinic acid. A mechanism is suggested to account for the formation of enolic esters and unsaturated lactones of enolized ketonic acids.

Syntheses of Enantiomeric N-(3-Hydroxy-2-phosphonomethoxypropyl) Derivatives of Purine and Pyrimidine Bases

1993 ◽  
Vol 58 (3) ◽  
pp. 649-674 ◽  
Author(s):  
Antonín Holý
Keyword(s):  
Benzoyl Chloride ◽  
Sodium Hydride ◽  
Cesium Carbonate ◽  
Amino Groups ◽  
Heterocyclic Base ◽  
Pyrimidine Bases ◽  
Derivatives Of ◽  
General Method

Methods of preparation of N-(3-hydroxy-2-phosphonomethoxypropyl) (HPMP) derivatives of (2S)- and (2R)-configuration (compounds I and XXVII, respectively) are described. The general method starts from the corresponding N-(2,3-dihydroxypropyl) derivatives which were converted either into the (R)-enantiomers XIII by reaction of the base with (R)-glycidol butyrate (XII) in the presence of cesium carbonate and subsequent methanolysis, or into the (S)-enantiomers XI by alkylation of the base with (R)-2,2-dimethyl-4-tosyloxymethyl-1,3-dioxolane (V) in the presence of the same reagent. The amino groups on the heterocyclic base in compounds XI and XIII were benzoylated by silylation followed by reaction with benzoyl chloride and the obtained N-benzoates XV and XVII on reaction with trityl chloride afforded the corresponding 3'-O-trityl derivatives XVI and XVIII. These compounds were condensed with bis(2-propyl) p-sulfonyloxymethylphosphonate (XXIII) in dimethylformamide in the presence of sodium hydride to give the fully protected diesters XXIV and XXVIII. These compounds could be selectively acid-hydrolyzed to remove the trityl group only under formation of compounds XXXV, or methanolyzed and then acid-hydrolyzed to remove the trityl and N-benzoyl groups and lead to compounds XXVI and XXX, or treated with bromotrimethylsilane to remove the trityl and 2-propyl group to give phosphonates of the type XXXI. All the three types of compounds were then converted into free phosphonates of the (S)-series (I) and the (R)-series (XXVII). Derivatives of cytosine (Ia, XXVIIa), adenine (Ib, XXVIIb), 2,6-diaminopurine (Ic, XXVIIc) and guanine (Id, XXVIId) were prepared. Condensation of the partially blocked adenine deriavtive XXXV with the tosyl derivative XXIII and subsequent deprotection afforded 9-(S)-(2,3-diphosphonomethoxy propyl)adenine (XLIII). Reaction of the same compound XXXV or its (R)-enantiomer XXXVIII with diethyl phosphonate , followed by deblocking, afforded 3'-O-phosphoryl derivatives (S)-HPMPA (XXXVII) and (R)-HPMPA (XL).

Derivatives of 4-(Aminomethyl)pyrrole-3-carboxylic Acid

1994 ◽  
Vol 47 (5) ◽  
pp. 975 ◽  
Author(s):  
DP Arnold ◽  
RFC Brown ◽  
LJ Nitschinsk ◽  
P Perlmutter ◽  
HK Tope
Keyword(s):  
Carboxylic Acid ◽  
Ethyl Esters ◽  
Tosylmethyl Isocyanide ◽  
Derivatives Of

Methyl and ethyl esters of 4-( aminomethyl )pyrrole-3-carboxylic acid were made through pyrrole synthesis with tosylmethyl isocyanide , but cyclization to a bicyclic lactam (1) was not achieved.

Preparation of some deuterium labelled 9- and/or 10-oxygenated derivatives of geraniol, geranial, nerol, and neral

1983 ◽  
Vol 61 (6) ◽  
pp. 1053-1059 ◽  
Author(s):  
J. Balsevich
Keyword(s):  
Selective Oxidation ◽  
Wittig Reaction ◽  
Dimethyl Acetal ◽  
Acidic Hydrolysis ◽  
Triphenyl Phosphonium ◽  
Isomeric Purity ◽  
Derivatives Of

The preparation of various deuterium labelled 9- and/or 10-oxygenated derivatives of geraniol, geranial, nerol, and neral is described. Wittig reaction of the tetrahydropyranyl ethers of (E)- and (Z)-1,1-dideutero-6-(triphenylphosphonium)-3-methyl-2-hexen-1-ol iodides (23 and 24) with the tetrahydropyranyl ethers of hydroxyacetone and 1,3-dihydroxyacetone afforded, after deprotection, C-1 dideuterated 9-hydroxygeraniol, 9-hydroxynerol, 9,10-dihydroxygeraniol, and 9,10-dihydroxynerol of high isomeric purity. Selective oxidation of these products allowed for the preparation of the corresponding derivatives possessing an aldehyde functionality at C-9 or C-1 and C-9. Wittig reaction of 23 and 24 with pyruvaldèhyde dimethyl acetal followed by acidic hydrolysis afforded C-1 dideuterated 10-oxogeraniol and 10-oxonerol, oxidation of which yielded C-1 deuterated 10-oxogeranial and 10-oxoneral. Wittig reaction of (E)- and (Z)-1,1-dideutero-6-(triphenyl-phosphonium)-3-methyl-2-hexen-1-ol iodides (49 and 50) with 1,1,3,3-tetraethoxyacetone afforded C-1 dideuterated 9,9,10,10-tetraethoxygeraniol and 9,9.10,10-tetraethoxynerol, oxidation of which provided C-1 deuterated 9,9,10,10-tctraethoxygeranial and 9,9,10,10-tetraethoxyneral.

Synthesis of Cyclopropyl Amino Acid Derivatives

1992 ◽  
Vol 45 (2) ◽  
pp. 395 ◽  
Author(s):  
CJ Easton ◽  
EW Tan ◽  
CM Ward
Keyword(s):  
Amino Acid ◽  
Sodium Hydride ◽  
Side Chain ◽  
Amino Acid Derivatives ◽  
Protected Amino Acid ◽  
Derivatives Of

Derivatives of α,β-methanovaline, α,β-methanophenylalanine and β-methyl-αβmethanoalanine have been prepared by regioselective side-chain functionalization of suitably protected amino acid derivatives, followed by cyclization with either sodium hydride or 1,8-diazabicyclo[5.4.O]undec-7-ene. The approach used in this work illustrates a method for the synthesis of cyclopropyl amino acid derivatives which is complementary to existing procedures.

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