Regioselective synthesis of substituted thieno[2,3-b]pyrimidines and pyrido[3′,2′:4,5]thienopyrimidines and their [3,2-d]selenopheno analogs from 3-cyanopyridine-2(1H)-thiones, 3-cyano-pyridine-2(1H)-selenones,and N-cyanochloracetamidine

3-Cyanopyridine-2(1H)-thiones and 3-cyano-2(1H)-selenones undergo heteroannelation with N-cyano-chloracetarnidine to give thieno[2, 3-b]pyridines,selenopheno[2, 3-b]pyridines, 2, 4-diantinopyrido-[3, 2:4, 5]thieno[3, 2-d]pyritnidines, and 2, 4-diamittopyrido[3, 2:4, 5]selenopheno[3, 2-d]pyritnidines, which were converted to compounds containing triazine, anzinopyrimidine, and pyrimidinedione rings.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 122–132, January, 1994.     

New convenient synthesis of substituted 6,9-dihydropyrido[3′,2′:4,5]thieno[3,2-b]pyridines and 6,9-dihydropyrido[3′,2′:4,5]thieno[3,2-d]pyrimidines

1,4-Dihydro-3-cyano-2-pyridinethiolates react with 2-bromo-l-(4-bromophenyl)ethylidenemalononitrile or N-cyanochloracetanudine to give 6, 9-dihydropyrido[3, 2': 4, 5]thieno[3. 2-b]pyridines or 6, 9-dihydropyrido-[3.2:4.5Jthieno(3,2-d]pyrimidines, respectively.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 553–556, April, 1996.     

IR absorption spectra and structure of 4-cyano-4′,-p-alkoxybiphenyls

The IR absorption spectra of 4-cyano-4,-p-alkoxybiphenyls were investigated experimentally (in the range 100–3200 cm^–1 at 100–400 K), and they were interpreted on the basis of a calculation of the frequencies, forms, and intensities of the normal vibrations of various conformers of the propyloxycyanobiphenyl molecule. Temperature and phase changes in the parameters of the IR spectrum are explained by a change in the conformational composition and intermolecular interactions in the investigated liquid crystals.Institute of Physics, Ukrainian Academy of Sciences. Saratov State University. Translated from Zhurnal Strukturnoi Khimii, Vol. 34, No. 2, pp. 105–111, January–February, 1993.     

IR spectroscopic study of the conformational lability of 4′-ethyl-4-cyanobiphenyl

The conformational lability of 4-ethyl-4-cyanobiphenyl molecules in solid crystal (SC) and isotropic liquid (IL) states was investigated by IR spectroscopic techniques (experiment and theory). IR absorption spectra were measured at 28°C–95°C in the frequency range 400 cm^–1–4000 cm^–1. Spectrum simulation was performed using the fragment method with allowance for the conformational fluctuations of molecules. The experimental and calculated spectra were compared and analyzed, and it was shown that in the IL, the samples are mixtures of conformers. The temperature changes in the spectra in the stated range are caused by the conformational lability of molecules.Original Russian Text Copyright © 2004 by L. M. Babkov, I. I. Gnatyuk, G. A. Puchkovskaya, and S. V. TrukhachevTranslated from Zhurnal Strukturnoi Khimii, Vol. 45, No. 3, pp. 398–405, May–June, 2004.     

Investigation of the process of polyimide formation from complexes of the diester of benzophenonetetracarboxylic acid with diamines

The kinetics of thermal imidization of the H-complexes derived from the diethyl ester of 3,3,4,4-benzophenonetetracarboxylic acid (EBZP) and various diamines have been studied. A comparison of kinetic parameters obtained for the imidization of H-complexes based on ethyl or methyl esters of this acid has disclosed the differences in the behavior of each of the two H-bonds and the contribution of each bond to the mechanism of polyimide formation from the respective H-complexes.For part 5, see ref.¹ Translated fromIzyestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 300–303, February, 1993.     

Tricyclic heteroaromatic ring systems III. Synthesis of 1H,6H-dipyrazolo[3,4-b:3′,4′-d]pyridin-3-ones

The reaction of hydrazines with substituted ethyl 4-chloro-1H-pyrazolo[3,4-b]pyridine-3-carboxylates leads to the formation of 1H,6H-dipyrazolo[3,4-b:3,4-d]pyridin-3-ones.

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Tricyclische heteroaromatische Ringsysteme, III. Synthese von 1H,6H-Dipyrazolo[3,4,-b:3,4-d]pyridin-3-onen (Kurze Mitteilung)

Zusammenfassung Die im Titel genannten Verbindungen wurden durch die Reaktion von Hydrazinen mit substituierten Ethyl-4-chlor-1H-pyrazolo[3,4-b]pyridin-3-carboxylaten dargestellt.

     

Synthesen in der Pyridazin-Reihe, 31. Mitt.: Über einige neue polycyclische Azolo- und Azinopyridazine

Zusammenfassung Synthesen von verschiedenen neuen polyazaheterocyclischen Systemen, wie 11H-Imidazo[1,22,3]pyridazino[6,1-b]-chinazolin-11-on (3), 11H-s-Triazolo[4,32,3]pyridazino[6,1-b]chinazolin-11-on (4), der Isomeren 4H-Pyrido[2,34,5]-pyridazino[6,1-c]-as-triazin (6) und 4H-Pyrido[3,24,5]-pyridazino[6,1-c]-as-triazin (9), Pyrido[3,24,5]pyridazino[1,6-b]benzimidazol (14) sowie Pyrido[3,24,5]-s-triazolo[4,32,3]pyridazino[1,6-a]benzimidazol (15) werden beschrieben.

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Syntheses of pyridazines, XXXI: Some new polycyclic azolo and azino-pyridazines

Syntheses of several new polyazaheterocyclic systems are described, i.e. 11H-Imidazo[1,22,3]pyridazino[6,1-b]quinazolin-11-one (3), 11H-s-Triazolo[4,32,3]pyridazino[6,1-b]quinazolin-11-one (4), the isomeric 4H-Pyrido[2,34,5]pyridazino[6,1-c]-as-triazine (6) and 4H-Pyrido[3,24,5]pyridazino[6,1-c]-as-triazine (9), Pyrido[3,24,5]pyridazino[1,6-b]-benzimidazole (14) and Pyrido[3,24,5]-s-triazolo[4,32,3]pyridazino[1,6-a]benzimidazole (15).

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Heterocyclen, 69. Mitt.     

Synthesis of new pyridazino[4′,3′:4,5]-thieno[3,2-d]-1,2,3-triazine and pyrimido[4′,5′:4,5]thieno[2,3-c]pyridazine derivatives

Summary 8,9-Diphenylpyridazino[4,3:4,5]thieno[3,2-d]-1,2,3-triazin-4(3H)-one (2), 3-substituted 8,9-diphenylpyridazino[4,3:4,5]thieno[3,2-d]-1,2,3-triazin-4(3H)-ones (3a–c), 3,4-diphenylpyrimido[4,5:4,5]thieno[2,3-c]pyridazin-8(7H)-one (4), 8-chloro-3,4-diphenylpyrimido[4,5:4,5]thieno[2,3-c]pyridazine (5), 8-substituted 3,4-diphenylpyrimido[4,5:4,5]thieno[2,3-c]pyridazines (6a–h) and 7-substituted 3,4-diphenylpyrimido[4,5:4,5]thieno[2,3-c]pyridazin-8(7H)-ones(7a–c) were synthesized from 5-amino-3,4-diphenylthieno[2,3-c]pyridazine-6-carboxamide (1).

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Synthese neuer Pyridazino[4,3:4,5]thieno[3,2-d]-1,2,3-triazin-und Pyrimido[4,5:4,5]thieno[2,3-c]pyridazin-Derivate

Zusammenfassung Folgende Verbindungen wurden ausgehend von 5-Amino-3,4-diphenylthieno[2,3-c]pyridazin-6-carboxamid (1) synthetisiert: 8,9-Diphenylpyridazino[4,3:4,5]thieno[3,2-d]-1,2,3-triazin-4(3H)-on (2), 3-substituierte 8,9-Diphenylpyridazino[4,3:4,5]thieno[3,2-d]-1,2,3-triazin-4(3H)-one (3a–c), 3,4-Diphenylpyrimido[4,5:4,5]thieno[2,3-c]pyridazin-8[7H]-on (4), 8-Chlor-3,4-diphenylpyrimido[4,5:4,5]thieno[2,3-c]pyridazin (5), 8-substituierte 3,4-Diphenylpyrimido[4,5:4,5]thieno[2,3-c]pyridazine (6a–h) und 7-substituierte 3,4-Diphenylpyrimido[4,5:4,5]thieno[2,3-c]pyridazin-8(7H)-one (7a–c).

     

Über Heterocyclen, 22. Mitt.: 3,4,6,7-Tetrahydro-5H-pyrrolo[3,4-d]pyrimidin-2(1H), 5-dione

Zusammenfassung Tetrahydro-6-brommethyl-2-oxopyrimidin-5-carbonsäureester reagieren mit Ammoniak bzw. Benzylamin zu Tetrahydro-5H-pyrrolo[3,4-d]pyrimidin-2(1H), 5-dionen. Mit 2-Aminopyridin (A) bilden sich Tetrahydro-6-(2-pyridylaminomethyl)-2-oxopyrimidin-5-carbonsäureester, Tetrahydro-5H-pyrrolo[3,4-d]pyrimidin-2(1H), 5-dione sowie 5-Äthoxycarbony]-2,3,5,6-tetrahydro-2-oxospiro(pyrimidin-4(1H), 2(3H)-1H-imidazo[1,2-a]pyridinium)bromide.

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Heterocycles XXII: 3.4.6.7-Tetrahydro-5H-pyrrolo [3.4-d]-pyrimidine-2(1H)-5-diones

Tetrahydro-6-bromomethyl-2-oxopyrimidine-5-carboxylates react with ammonia and benzylamine, resp., to give tetrahydro-5H-pyrrolo[3.4-d]pyrimidin-2(1H), 5-diones. With 2-aminopyridine (A) tetrahydro-6-(2-pyridylaminomethyl)-2-oxopyrimidine-5-carboxylates, tetrahydro-5H-pyrrolo[3.4-d]pyrimidine-2(1H). 5-diones as well as 5-ethoxycarbonyl-2.3.5.6-tetrahydro-2-oxospiro(pyrimidin-4(1H)-2(3H)-1H-imidazo[1.2-a]-pyridinium) bromides are formed.

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Herrn Prof. Dr.O. Hromatka zum 65. Geburtstag gewidmet.     

Synthesen von Heterocyclen, 81. Mitt.: Über substituierte Glyoxalhydrazone

Zusammenfassung 3-Phenylazo-4-hydroxy-2-oxo-indeno[1,2-b]pyran (4) läßt sich durch Erhitzen mit verd. Lauge zum 3-Hydroxyindenyl-(2)-glyoxal-2-phenylhydrazon (11) hydrolysieren, welches mit Phenylhydrazin unter Ringschluß zum 1,4-Dihydro-1-phenylindeno-[1,2-c]pyrazol-(3)-aldehydphenylhydrazon (21) reagiert.

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3-Phenylazo-4-hydroxy-2-oxo-indeno[1,2-b]pyran (4) is hydrolysed by heating in aqueous sodium hydroxide solution to 3-hydroxyindenyl-(2)-glyoxal-2-phenylhydrazone (11). This compound reacts with phenylhydrazine under ring closure to 1,4-dihydro-1-phenylindeno[1,2-c]pyrazol-(3)-aldehyde phenylhydrazone (21).

     

4,4′-Dipyridyl and 2,2′-dipyridyl complexes of rare-earth perchlorates

4,4-Dipyridyl and 2,2-dipyridyl complexes of rare-earth perchlorates of the formulaLn(4-dipy)₈(ClO₄)₃HClO₄ · 4H₂O (Ln=La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Yb, Lu, Y, 4-dipy=4,4-dipyridyl) andLn(2-dipy)₃(ClO₄)₃ · 6H₂O (Ln=Pr, Sm, Eu, Gd, Tb, Dy, Ho, Er, Yb, Lu, Y, 2-dipy = 2,2-dipyridyl) have been synthesized. The IR spectra of these compounds and other physical properties are discussed.

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4,4-Dipyridyl- und 2,2-Dipyridylkomplexe von Seltenerdmetallperchloraten

Zusammenfassung Es wurden 4,4-Dipyridylkomplexe des TypsLn(4-dipy)₈(ClO₄)₃HClO₄ · · 4 H₂O mitLn=La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Yb, Lu, Y und 2,2-Dipyridylkomplexe des TypsLn(2-dipy)₃(ClO₄)₃ · 6 H₂O mitLn=Pr, Sm, Eu, Gd, Tb, Dy, Ho, Er, Yb, Lu und Y dargestellt. Die IR-Spektren und andere physikalische Eigenschaften werden diskutiert.

     

Molecular orbital calculations on the conformation of nucleic acids and their constituents

The conformational properties of the furanose ring of purine- and pyrimidine--nucleosides and-nucleotides are studied quantum-mechanically with the help of the PCILO method, using the pseudorotational concept. The computations point to the existence of two stable conformational zones centered around the C(3)-endo and C(2)-endo conformations which in the isolated furanose ring are separated by barriers of the order of 4 kcal/mole. In nucleosides one of the barriers (the one running through the O(1)-exo-C(2)-exo path) becomes very high. A detailed study is made of the relation between the phase angle of pseudorotation, P, and the torsion angle about the glycosyl bond, _CN. A very satisfactory agreement with the available experimental data is observed.

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Zusammenfassung Die Konformationseigenschaften des Furanoserings in -Nucleosiden und Nucleotiden von Purin und Pyrimidin werden nach der PCILO-Methode unter Berücksichtigung der pseudorotatorischen Betrachtungsweise studiert. Die Rechnung läßt auf die Existenz zweier stabiler Konformationszonen schließen, die in der Umgebung der C(2)-endo und der C(3)-endo Konformationen liegen, und die im isolierten Furanosering durch Energiebarrieren der Größenordnung von 4 kcal/mol voneinander getrennt sind. In Nucleosiden wird eine der Barrieren (die durch den Weg O(1)-exo-C(2)-exo gekennzeichnete) sehr hoch. Die Relation zwischen dem Phasenwinkel der Pseudorotation, P, und dem Drehwinkel um die Glycosylbindung, _CN, wird einer eingehenden Untersuchung unterworfen. Man beobachtet eine sehr zufriedenstellende Übereinstimmung mit den verfügbaren experimentellen Daten.

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Résumé Les propriétés conformationnelles du noyau furanose des -nucleosides et nucleotides des purines et pyrimidines sont étudiées par la méthode PCILO en faisant appel au concept de la pseudorotation. Les calculs indiquent l'existence de deux zones de conformations stables, centrées autour des conformations C(2)-endo et C(3)-endo, qui sont dans le sucre isolé séparées par des barrières de l'ordre de 4 kcal/mole. Dans les nucleosides, l'une de ces barrières (celle qui passe par le chemin O(1)-exo-C(2)-exo) devient très élevée. Une étude détaillée est effectuée sur la relation entre l'angle de phase de la pseudorotation P et l'angle de torsion autour de la liaison glycosylique, _CN. Un excellent accord avec les données expérimentales disponibles est observé.

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This research was supported by the R.C.P. 173 and the A.T.P. A 655-2303 of the C.N.R.S.     

X-ray and IR spectroscopic studies of specific intermolecular interactions inN′-substituted isonicotinohydrazides

_N-Thenylidene- andN-(o-nitrobenzylidene)hydrazides of isonicotinic acid have been studied by X-ray structural analysis and IR spectroscopy. In the crystalline state, these molecules are linked through intermolecular N—H ... Np_y hydrogen bonds. Carbonyl groups are not involved in intermolecular hydrogen bonds. However, it was found that the C=O group participates in an attractive interaction with the sulfur atom of the thiophene group. The energy of this interaction is comparable with the energies of intermolecular C=O ... H—N hydrogen bonds in amides.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 896–900, April, 1996.     

New approach to the functionalization of δ-carboline derivatives

The possibility of transformation of 3-cyano-1-p-nitrophenyl--carbolin-2-one into 2-amino-3-cyano-1-p-nitrophenyl-1H-pyrido[3,2-b]indole derivatives and 2-imino-3-cyano-1-p-nitrophenyl-5H-pyrido[3,2-b]indole derivatives (-carbolines) is demonstrated. Methylation of 1-p-nitrophenyl-2-piperidino-1H--carboline followed by treatment with acetone in an alkaline medium yields 4-acetonyl-5-methyl-1,4-dihydro-5H-pyrido[3,2-b]indole derivative. The rearrangement of 2-arylimino-3-cyano-1-p-nitrophenyl-5H-pyrido[3,2-b]indoles into 2-(aryl)nitrophenylamino-3-cyano-5H-pyrido[3,2-b]indoles was accomplished on heating above the melting point or on treatment with potassium tert-butoxide. The structures of the resulting compounds were proved by ¹H and ¹³C NMR spectroscopy and X-ray diffraction analysis.     

Molecular orbital studies on nucleoside antibiotics X. Conformation of nebularine and isoguanosine

Summary Conformational properties of two nucleoside analogs, namely nebularine and isoguanosine have been investigated by using PCILO (Perturbative Configuration Interaction using Localized Orbitals) method. Nebularine (9--ribofurnosyl purine) is a naturally occurring purine nucleoside which is structurally similar to adenosine and it inhibits the growth of tumor cells and influenza B virus. Isoguanosine is one of the two naturally occurring analogs of guanosine. Both C2-endo and C3-endo sugar puckerings have been considered for both the molecules with preselected values of torsion angles around C2–O2 and C5–O5 bonds. The results indicate that nebularine has conformational preferences very similar to those of its parent nucleoside, adenosine; whereas the conformational properties of isoguanosine are very different from those of guanosine as well as adenosine. The important implications of these results have been discussed in terms of the biological activity of these molecules.     

4,4′-Dipyridyl complexes of rare-earth thiocyanates

4,4-Dipyridyl complexes of rare-earth thiocyanates of the formulaLn(4-dipy)₂(NCS)₃·5H₂O (Ln = La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Yb, Lu, Y, 4-dipy = 4,4-dipyridyl) have been synthesized. The IR spectra of these compounds and other physical properties are discussed. The thermal decomposition of some compounds (in the order Gd ÷ Lu) has been investigated.

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4,4-Dipyridylkomplexe von Seltenerdmetallthiocyanaten

Zusammenfassung Es wurden 4,4-Dipyridylkomplexe des TypesLn(4-dipy)₂(NCS)₃·5H₂O mitLn = La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Yb, Lu und Y dargestellt. Die IR-Spektren und andere physikalische Eigenschaften werden diskutiert und die thermische Zersetzung von einigen Verbindungen (in der Reihe Gd ÷ Lu) untersucht.

     

Synthesis and reactions of new 4-chloro-2-methylpyrimidino[4′,5′:4,5]thiazolo[3,2-a]-benzimidazoles

Summary 4-Chloro-2-methylpyrimidino[4,5:4,5]thiazolo[3,2-a]benzimidazole (3) was prepared by chlorination of2 which could also be converted directly to 2-methylpyrimidino[4,5:4,5]-thiazolo[3,2-a]benzimidazol-4-thiol (4). Nucleophilic substitution of3 with alcohols, phenols, primary amines, secondary amines, sodium azide, and mercaptoacetic acid gave the corresponding derivatives. The thiol derivative4 was reacted with alkyl/aralkyl halides, phenacyl bromide derivatives, bromoacetone, chloroanilides, bromomalonic ester, and ethyl bromoacetate to afford compounds of potential pharmacological interest.

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Synthese und Reaktionen neuer 4-Chlor-2-methylpyrimidino[4,5:4,5]thiazolo[3,2-a]benzimidazole

Zusammenfassung 4-Chlor-2-methylpyrimidino[4,5:4,5]thiazolo[3,2-a]benzimidazol (3) wurde durch Chlorierung von2, welches auch direkt zu 2-Methylpyrimidino[4,5:5,4]thiazolo[3,2-a]-benzimidazol-4-thiol (4) umgesetzt werden kann, hergestellt. Nucleophile Substitution von3 mit Alkoholen, Phenolen, primären Aminen, sekundären Aminen, Natriumazid und Mercaptoessigsäure ergab die entsprechenden Derivate. Das Thiolderivat4 wurde mit Alkyl/Alkarylhalogeniden, Phenacylbromidderivaten, Bromaceton, Chloraniliden, Brommalonsäureester und Bromessigsäureethylester zu potentiell pharmakologisch interessanten Verbindungen umgesetzt.

     

Vibrational spectra and the structure of long-chain aliphatic compounds

Polymorphism and the structure of mesomorphous states of long-chain aliphatic compounds (LAC) have been studied by vibrational spectroscopy (theory, experiment) using calorimetry, polarizing microscopy (PM), and X-ray diffraction (XRD) analysis as auxiliary methods. LAC are represented by homologous series of alkyl- and alkoxybenzoic acids, alkylcyclohexanecarboxylic acids, their completely or partially fluoroalkyl-substituted analogs, and 4-cyano-4′-(n-alkoxy)biphenyls. The studies were performed at 77–500 K. IR absorption and Raman spectra were measured at 30–4000 cm⁻¹. The compounds are characterized by conformational polymorphism. The molecules and their H-complexes undergo structural rearrangements during phase and conformational transitions. In the course of the rearrangements, alkyl and fluoroalkyl radicals (AR and FAR) are twisted, and carboxyl groups are disordered. The rearrangements dictate the structure of mesophases, which are mostly formed of H-complexes consisting of dimers, monomers, and open associates. N. G. Chernyshevskii Saratov State University. Institute of Physics, Ukrainian Academy of Sciences. Translated fromZhurnal Strukturnoi Khimii, Vol. 36, No. 2, pp. 338–344, March–April, 1995. Translated by L. Smolina     

Synthesis and Structural Studies of Group 2B Transition Metal Complexes with the Bulky Nitrogen Ligand Bis[<Emphasis Type="Italic">N</Emphasis>-(2,6-diisopropylphenyl) imino]acenaphthene

Summary. Group 2B transition metal complexes of bis[N-(2,6-diisopropylphenyl)imino]acenaphthene (o,o-iPr₂C₆H₃-BIAN), namely, [Hg(o,o-iPr₂C₆H₃-BIAN)Cl₂] (1), [Zn(o,o-iPr₂C₆H₃-BIAN)₂](ClO₄)₂ (2), and [Cd(o,o-iPr₂C₆H₃-BIAN)₂](ClO₄)₂ (3) have been synthesized and characterized. In complexes 2 and 3, IR, NMR, and conductivity measurements confirm the coordination of two (o,o-iPr₂C₆H₃-BIAN) ligands to the metal center with two discrete perchlorate anions. X-Ray crystal structure of 1 indicates a distorted tetrahedral geometry with two nitrogen atoms from (o,o-iPr₂C₆H₃-BIAN) ligand and two chloride atoms coordinating to the Hg(II) center.     

Stereochemistry of planarchiral compounds,part XII: Absolute chiralities and X-ray crystal structures of 2,2′-Bi(1,6-methano[10]annulenyl)s

Summary The absolute chirality of the dextrorotatory main rotamer of 10,10-dibromo-2,2-bi(1,6-methano[10]annulenyl) (1 b), obtained by low temperature chromatography or by crystallisation of the (+)-enantiomer of1 b, was established by observation of anomalous X-ray diffraction as (+)-(R) _p (R) _a (R) _p -1b. This result was confirmed by reduction of (+)-1 b to a dextrorotatory 2,2-bi(1,6-methano[10]annulenyl) (1 a), which in turn was accessible by coupling of (–)-2-Bromo-1,6-methano[10]annulene (3) of known chirality (S) _p and, moreover, by enantioselective chromatography of1 a on triacetyl cellulose in ethanol. This correlation determines also the chirality of (+)-1 a as (S) _p (S) _p .According to the X-ray analyses the main rotamer of (+)-1 b and the meso-form (2 b) adopt crystal structures in which the bromine atoms come close to the CH₂-bridges. The torsional angles around the 2,2-bonds vary between 33°, 53° and 65° for (+)-1 b, racem.1 b and the mesoform2 b, respectively.Dedicated to Prof. Dr. G. Snatzke (Bochum) with cordial wishes on the occasion of the 60th anniversary of his birthday