7-O-Alkyl derivatives of daunomycinone

1984 ◽  
Vol 49 (1) ◽  
pp. 313-319 ◽  
Author(s):  
Věra Přikrylová ◽  
Petr Sedmera ◽  
Josef V. Jizba ◽  
Jindřich Vokoun ◽  
Helena Lipavská ◽  
...  
Keyword(s):  
H Nmr ◽  
Toluenesulfonic Acid ◽  
Alkyl Derivatives ◽  
Derivatives Of

Reaction of daunomycinone (I) with alcohols and p-toluenesulfonic acid produces a mixture (~3 : 1) of its (7S)- and (7R)-O-alkyl derivatives II-IX. According to the 1H NMR evidence, the alicyclic ring exists in the 9H8 conformation in (7R)-O-alkyl derivatives, on the contrary to (7S)-epimers and 7-epi-daunomycinone that adopt the 8H9 conformation.

Synthesis of Optically Active N6-Alkyl Derivatives of (R)-3-(Adenin-9-yl)-2-hydroxypropanoic Acid and Related Compounds

2003 ◽  
Vol 68 (5) ◽  
pp. 931-950 ◽  
Author(s):  
Marcela Krečmerová ◽  
Miloš Buděšínský ◽  
Milena Masojídková ◽  
Antonín Holý
Keyword(s):  
Nmr Spectra ◽  
Enantiomeric Purity ◽  
Optically Active ◽  
Secondary Amines ◽  
H Nmr ◽  
Alkyl Derivatives ◽  
Optically Pure ◽  
Derivatives Of ◽  
Related Compounds

Reaction of ethyl (R)-oxiranecarboxylate (2a) with various nucleobases (adenine, 6-chloropurine, thymine, cytosine, N6-benzoyladenine, 4-methoxy-5-methylpyrimidin-2(1H)-one and 4-methoxypyrimidin-2(1H)-one) afforded ethyl 3-substituted-2-hydroxypropanoates 4-10. Enantioselectivity of this reaction is dependent on the type of the base: 6-chloropurine, N6-benzoyladenine, 4-methoxy-5-methylpyrimidin-2(1H)-one, thymine and cytosine gave optically pure R enantiomers. In other cases, partial or complete racemization occurred. Optically pure ethyl (R)-3-(6-chloropurin-9-yl)-2-hydroxypropanoate (5a) was hydrolyzed to give (R)-3-(6-chloropurin-9-yl)-2-hydroxypropanoic acid (11). Reactions of 11 with various primary or secondary amines led to N6-substituted (R)-3-(adenin-9-yl)-2-hydroxypropanoic acids 14-19. Enantiomeric purity was determined from 1H NMR spectra measured in the presence of (-)-(R)-1-(9-anthryl)-2,2,2-trifluoroethan-1-ol.

Purine Nucleoside Analogues. 11. An Alternative Synthesis of N- and O-Alkyl Derivatives of 9- and 7-[(2-Acetoxyethoxy)methyl]-N2-acetylguanine

1999 ◽  
Vol 64 (4) ◽  
pp. 685-695 ◽  
Author(s):  
Marina Madre ◽  
Natella Panchenko ◽  
Alexander Golbraikh ◽  
Regina Zhuk ◽  
Upendra K. Pandit ◽  
...  
Keyword(s):  
Nmr Spectra ◽  
Room Temperature ◽  
Purine Nucleoside ◽  
Nucleoside Analogues ◽  
Alternative Synthesis ◽  
Restricted Rotation ◽  
H Nmr ◽  
Alkyl Derivatives ◽  
Derivatives Of ◽  
Conformational Calculations

Alkylations of 9- and 7-[(2-acetoxyethoxy)methyl]-N2-acetylguanine with alkyl halogenides in the presence of base have been investigated affording a new route to the preparation of 1,N2-dimethyl- as well as O6-benzyl-9(7)-alkoxyalkylguanines. 1H NMR spectra revealed that the 1,N2-dimethyl derivatives exist as mixtures of two conformers at room temperature due to the restricted rotation about the C2-N2 bond. These findings agreed with conformational calculations.

Synthesis and characterization of organometallic hydro-tris-pyrazolylborate derivatives of scandium via alkane elimination

1997 ◽  
Vol 75 (6) ◽  
pp. 702-711 ◽  
Author(s):  
James Blackwell ◽  
Corinne Lehr ◽  
Yimin Sun ◽  
Warren E. Piers ◽  
Susan D. Pearce-Batchilder ◽  
...  
Keyword(s):  
Monoclinic Space Group ◽  
Triclinic Space Group ◽  
Space Group ◽  
H Nmr ◽  
Alkyl Derivatives ◽  
Solid State Structures ◽  
Derivatives Of ◽  
Alkane Elimination

Reaction between the potassium salts of the hydro-tris-pyrazolylborate ligands TpMe'Me and TptBu'Me and the tris THF adduct of scandium trichloride lead to isolation of the scandium complexes (TpMe,Me)ScCl2(THF), 1a, and (TptBu,Me)ScCl2, 1b, in 65 and 49% yield, respectively. Subsequent reactions between 1a and 1b and alkyl lithium reagents RLi (R = Me, CH2SiMe3, and CH(SiMe3)2) gave the lithium salts of the Tp ligands as the major isolated products in all cases but one. The complex (TpMe,Me)Sc(CH2SiMe3)2(THF), 2a, could be obtained contaminated with at least 10% TpMe,MeLi via this methodology. A salt-free alkane elimination route to bis-trimethylsilylmethyl complexes 2a and the THF-free (TptBu,Me)Sc(CH2SiMe3)2, 2b, involving reaction between in situ generated Sc(CH2SiMe3)3(THF)2 and the protonated ligands, TpR,MeH, gave samples of the desired bis-alkyl derivatives in 67 and 87% yield, respectively. In solution, complexes 2a and 2b are both fluxional at room temperature. These dynamic processes were frozen out on the NMR time scale at lower temperatures and interpreted on the basis of the 1H NMR spectra obtained as well as information obtained from the solid state structures of both compounds, 2a: monoclinic, space group P21/c, a = 11.765(4) Ǻ, b = 14.8311(20) Ǻ, c = 20.891(5) Ǻ, β = 105.69(3)°, V = 3509.4(15) Ǻ3, Z = 4, R = 0.088, Rw = 0.082. 2b: triclinic, space group [Formula: see text], a = 11.9427(2) Ǻ, b = 20.3641(3) Ǻ, c = 26.5602(2) Ǻ, α = 112.192(1)°, β = 100.569(1)°, γ = 92.928(1)°, V = 5830.38(14) Ǻ3, Z = 6, R = 0.0500, Rw = 0.1137. Keywords: organoscandium complexes, hydro-tris-pyrazolylborate ligands, alkane elimination.

Monitoring the encapsulation of chlorin e6 derivatives into polymer carriers by NMR spectroscopy

2019 ◽  
Vol 23 (11n12) ◽  
pp. 1576-1586 ◽  
Author(s):  
Sara Pfister ◽  
Luca Sauser ◽  
Ilche Gjuroski ◽  
Julien Furrer ◽  
Martina Vermathen
Keyword(s):  
Relaxation Time ◽  
Nmr Spectroscopy ◽  
Core Region ◽  
Chlorin E6 ◽  
Polypropylene Glycol ◽  
Polymer Carriers ◽  
H Nmr ◽  
Line Shape Analysis ◽  
Dynamic Methods ◽  
Derivatives Of

The encapsulation of five derivatives of chlorin e6 with different hydrophobicity and aggregation properties into a series of five poloxamer-type triblock copolymer micelles (BCMs) with varying numbers of polyethylene and polypropylene glycol (PEG, PPG) units was monitored using 1H NMR spectroscopy. NMR chemical shift and line shape analysis, as well as dynamic methods including diffusion ordered spectroscopy (DOSY) and T1 and T2 relaxation time measurements of the chlorin and the polymer resonances, proved useful to assess the chlorin–BCM compatibility. The poloxamers had high capability to break up aggregates formed by chlorins up to intermediate hydrophobicity. Physically entrapped chlorins were always localized in the BCM core region. The loading capacity correlated with chlorin polarity for all poloxamers among which those with the lowest number of PPG units were most efficient. DOSY data revealed that relatively weakly aggregating chlorins partition between the aqueous bulk and micellar environment whereas more hydrophobic chlorins are well retained in the BCM core region, rendering these systems more stable. T1 and T2 relaxation time measurements indicated that motional freedom in the BCM core region contributes to encapsulation efficiency. The BCM corona dynamics were rather insensitive towards chlorin entrapment except for the poloxamers with short PEG chains. The presented data demonstrate that 1H NMR spectroscopy is a powerful complementary tool for probing the compatibility of porphyrinic compounds with polymeric carriers such as poloxamer BCMs, which is a prerequisite in the development of stable and highly efficient drug delivery systems suitable for medical applications like photodynamic therapy of tumors.

Polarized fluorescense of alkyl derivatives of fluorescein, MitoFluo and C8-Fl, in solutions with liposomes

2020 ◽  
Author(s):  
D.M. Beltukova ◽  
V.P. Belik ◽  
Y.N. Antonenko ◽  
A.A. Bogdanov ◽  
G.A. Korshunova ◽  
...  
Keyword(s):  
Alkyl Derivatives ◽  
Derivatives Of

Synthesis and reactivity of halide, hydride, and alkyl derivatives of (pentamethylcyclopentadienyl)(bisphosphine)iron(II)

1990 ◽  
Vol 9 (1) ◽  
pp. 260-265 ◽  
Author(s):  
Rocco A. Paciello ◽  
Juan M. Manriquez ◽  
John E. Bercaw
Keyword(s):  
Alkyl Derivatives ◽  
Derivatives Of

The Alkyl Derivatives of Halogen Phenols and their Bactericidal Action. II. Bromophenols

1933 ◽  
Vol 55 (11) ◽  
pp. 4657-4662 ◽  
Author(s):  
Emil Klarmann ◽  
Louis W. Gates ◽  
Vladimir A. Shternov ◽  
Philip H. Cox
Keyword(s):  
Bactericidal Action ◽  
Alkyl Derivatives ◽  
Derivatives Of

570. Compounds of potential pharmacological interest. Part IV. Aryl and alkyl derivatives of 1-aminoindane

1956 ◽  
pp. 2928 ◽  
Author(s):  
J. A. Barltrop ◽  
R. M. Acheson ◽  
P. G. Philpott ◽  
K. E. MacPhee ◽  
J. S. Hunt
Keyword(s):  
Alkyl Derivatives ◽  
Pharmacological Interest ◽  
Derivatives Of

Synthesis of amino acid derivatives of indole-3-acetic acid

2005 ◽  
Vol 2005 (10) ◽  
pp. 640-642 ◽  
Author(s):  
Ying Liu ◽  
Liang Zhao ◽  
Liang Liu ◽  
Lin-Yi Wei ◽  
Lu-Hua Lai
Keyword(s):  
Acetic Acid ◽  
Amino Acid ◽  
Amino Acid Derivatives ◽  
H Nmr ◽  
Derivatives Of ◽  
Indole 3 Acetic Acid

Amino acid derivatives of a modified indole-3-acetic acid have been synthesised. Fourteen new dipeptide-like compounds 3–4 were obtained and their structures were elucidated based on the IR, 1H NMR, MS spectra.

scholarly journals CHEMISTRY AND SYNTHESIS OF SOME DIHYDRO-2H-l,4-BENZOTHIAZINE DERIVATIVES

1966 ◽  
Vol 44 (11) ◽  
pp. 1247-1258 ◽  
Author(s):  
Raj Nandan Prasad ◽  
Karin Tietje
Keyword(s):  
Alkyl Halides ◽  
Reduction Product ◽  
Alkyl Derivatives ◽  
Reaction Proceeds ◽  
Thiazine Ring ◽  
Derivatives Of ◽  
Compound Xviii ◽  
Acyl Derivatives

The formation of 3-oxo-3,4-dihydro-2H-1,4-benzothiazine (IIIa) by cyclization of alkyl 2-haloacetamidophenyl sulfides (I) was investigated; it is proposed that the reaction proceeds via a six-membered sulfonium halide. The preparation of 4-alkyl derivatives of IIIa and of 4-alkyl and 4-acyl derivatives of its reduction product 3,4-dihydro-2H-1,4-benzothiazine (Va) is described. Acylation of Va was shown to proceed without opening of the thiazine ring. Preparation of the O-benzoyl, N-benzoyl, and O,N-dibenzoyl derivatives of 2-(β-hydroxyethyl-mercapto)aniline (VIII) has permitted clarification of the confusion in the literature with respect to the derivatives of Va and VIII. Compound XVIII, the 1,1-dioxide of IIIa, undergoes C-alkylation at the 2-position when treated with alkyl halides, rather than O-alkylation as previously suggested.

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