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The synthesis of aminodeoxybestatin and epi-aminodeoxybestatin [(2S,3R)- and (2R,3R)-2,3-di-amino-4-phenylbutanoyl-L-leucine; (2S,3R)- and (2R,3R)-DAPBA-L-Leu)], bestatin and epi-bestatin analogues, respectively, in which the hydroxy group has been replaced with an amino group, is described by two different methods. The first one involves the synthesis of bis-(N-Z)-DAPBA, by homologation of N-Z-phenylalanine, via a modified Strecker synthesis followed by subsequent coupling with the methyl ester of L-leucine and removal of the protecting groups. Following this procedure, 25% racemization at the C-3 centre of the DAPBA derivatives took place during the homologation reaction. The second method involves the stereospecific SN2 nucleophilic substitution of the 2-hydroxy group of (2R,3R)- and (2S,3R)-3-(benzyloxycarbonyl)amino-2-hydroxy-4-phenylbutanoyl-L-leucine methyl esters [(2R,3R)- and (2S,3R)-N-Z-AHPBA-L-Leu-OMe], and subsequent saponification, azido reduction and removal of the N-Z-protecting group. Replacement of the hydroxy group of bestatin and epi-bestatin with an amino group results in a decrease in their aminopeptidase (AP-B, AP-M and Leu-AP)-inhibitory potencies.

A bioactivity-guided approach was taken to identify the acetylcholinesterase (AChE) inhibitory agents in the ethanolic extract of CHUQUIRAGA ERINACEA D. Don. subsp. ERINACEA leaves using a bioautographic method. This permitted the isolation of the pentacyclic triterpenes calenduladiol ( 1), faradiol ( 2), heliantriol B2 ( 3), lupeol ( 4), and a mixture of α-and β-amyrin ( 5A and 5B) as active constituents. Pseudotaraxasterol ( 6) and taraxasterol ( 7) were also isolated from this extract and showed no activity at the same analytical conditions. Compound 1 showed the highest AChE inhibitory activity with 31.2 % of inhibition at 0.5 mM. Looking forward to improve the water solubility of the active compounds, the sodium sulfate ester of 1 was prepared by reaction with the (CH 3 ) 3 N.SO 3 complex. The semisynthetic derivative disodium calenduladiol disulfate ( 8) elicited higher AChE inhibition than 1 with 94.1 % of inhibition at 0.5 mM (IC 50 = 0.190 ± 0.003 mM). Compounds 1, 2, 3, 5, 6, and 7 are reported here for the first time in C. ERINACEA. This is the first report of AChE inhibition from calenduladiol ( 1) as well as from a sulfate derived from a natural product.

Nucleoamino acids, wherein D- and L-penicillamine and D-and L-cysteine are attached to uridine or thymidine through a carboxylic ester linkage, have been synthesized and evaluated as antivirals and aminopeptidase B (AP-B) inhibitors. The coupling of the α-amino-β-mercapto acids, N,S-protected as N-formylthiazolidines, to 2′,3′-O-isopropylideneuridine, 3′-O-acetylthymidine, 5′-O-tritylthymidine, and thymidine was achieved via the mixed anhydride formed from N,N-bis-(2-oxooxazolidin-3-yl)phosphorodiamidic chloride and the corresponding protected amino acid in the presence of 4-(dimethylamino)pyridine. Treatment of the protected compounds with 1 mol dm–3-HCl in refluxing MeOH, under argon, afforded the corresponding deprotected nucleoamino acids free of racemization. Neither the compounds herein described nor D-penicillamine showed anti-HIV-1 activity in MT-4 cells or antiviral activity against some other viruses at concentrations below the cytotoxicity threshold. Penicillamine and cysteine monoesters were equipotent with the corresponding free amino acid in inhibiting AP-B with an IC50 in the 10–4 mol dm–3 range, while the bis-(α-amino-β-mercaptoacyl)thymidine derivatives were approximately twice as potent as the monoesters.

5′-O-[N-(Aminoacyl)sulfamoyl]-uridines and -thymidines 4a-12a and 4b-12b have been synthesized and tested against Herpes Simplex virus type 2 (HSV-2) and as cytostatics. Condensation of 2′,3′-O-isopropylidene-5′-O-sulfamoyluridine and 3′-O-acetyl-5′-O-sulfamoylthymidine with the N-hydroxysuccinimide esters of Boc-L-Ser(Bzl), (2R, 3S)-3-benzyloxycarbonylamino-2-hydroxy-4-phenylbuta-noic acid [(2R, 3S-N-Z-AHPBA], (2R, 3S) and (2S, 3R)-N-Boc-AHPBA gave 4a,b-7a,b, which after removal of the protecting groups provided 1Oa,b-12a,b. A study of the selective removal of the O-Bzl protecting group from the L-Ser derivatives 4a,b, without hydrogenation of the pyrimidine ring, has been carried out. Only the fully protected uridine derivatives 4a-7a did exhibit high anti-HSV-2 activity, and none of the synthesized compounds showed significant cytostatic activity against HeLa cells cultures.

El objetivo del presente trabajo fue determinar la prevalencia, intensidad media y abundancia media de ectoparásitos en palomas domésticas (Columba livia) comercializadas en un mercado de la ciudad de Lima, Perú. Se analizaron 29 ejemplares (17 machos y 12 hembras). Se inspeccionó la superficie externa de la cabeza, cuello, pecho, dorso y alas, determinando que el 93.1% (14.9 ± 15.8 de abundancia media total) de las palomas estuvieron infestadas con uno o más ectoparásitos; asimismo, el 100 de los machos y 83.3% de las hembras estuvieron parasitados. Se identificaron siete especies de ectoparásitos, de los cuales cinco corresponden al Orden Mallophaga (Columbicola columbae [82.8%], Menopon gallinae [48.3%] Goniodes gigas [31%], Menacanthus stramineus [17.2%] y Lipeurus caponis [6.9%]), uno al Orden Diptera (Pseudolynchia canariensis [10.3%]), y uno al Orden Siphonapetra (Echidnophaga gallinacea [3.4%]). El mayor número de malófagos fue encontrado sobre las plumas de las alas y el pecho. En las asociaciones de parásitos, se encontró 28% de monoparasitismo, 28% de biparasitismo, 34% de triparasitismo y 3% de tetraparasitismo. C. columbae fue el ectoparásito con mayor prevalencia (82.8%). Además, se reporta por primera vez a Menacanthus stramineus y Lipeurus caponis como ectoparásitos de C. livia en el Perú., The aim of this study was to determine the prevalence, average intensity and mean abundance of ectoparasites in domestic pigeons (Columba livia). A total of 29 specimens were analyzed (17 males and 12 females). External surface of head, neck, chest, back and wings were examined, determining that 93.1% (14.9 ± 15.8 of total mean abundance) of pigeons were infected with one or more ectoparasites. All males and 83.3% of females were parasitized. Seven species of ectoparasites were identified, where five correspond to Order Mallophaga (Columbicola columbae [82.8%], Menopon gallinae [48.3%] Goniodes gigas [31%], Menacanthus stramineus [17.2%] and Lipeurus caponis [6.9%]), one to Order Diptera (Pseudolynchia canariensis [10.3%]), and one to Order Siphonapetra (Echidnophaga gallinacea [3.4%]). The largest number of mallophagans was found on the feathers of the wings and chest. Among associations, the monoparasitism was present in 28%, biparasitism in 28%, triparasitism in 34% and tetraparasitism in 3% of the pigeons. C. columbae was the most prevalent ectoparasite (82.8%). Besides, Menacanthus stramineus and Lipeurus caponis are reported for the first time as ectoparasites of Columba livia in Peru.

A number of new 2′,3′-fused oxirane derivatives were synthesized for structure–activity relationship study. Many of these derivatives exhibit high potency against Candida spp. In addition, sordarin manno epoxide derivative 6 presents in vivo therapeutic effect in mice and is considered a promising antifungal lead within this series.

4 pages, 1 figure, 1 table, 2 schemes.-- Printed version published Sep 17, 2001., The use of polymer-bound guanidine 6b or polymer-bound phosphazene 6c significantly improve the yield of the Hofmann elimination step in the preparation of tertiary amines using REM resin, providing products with superior purities and free from contamination with trialkylammonium salts.

Se realiza la reconstrucción de la experiencias vivida durante la formación y desarrollo del proyecto pedagógico de educación física en las escuelas de básica primaria malta y Pilsen, durante el periodo 1996-1997. Se describe el origen del convenio interinstitucional que dio inicio a la experiencia, forma como se organizaron los practicantes con el asesor para adelantar el proyecto pedagógico en educación física, el proceso desarrollado en los diferentes grados escolares en cuanto a enfoque, objetivos, metodología, contenidos y evaluación. Finalmente, se presenta una reflexión del grupo sobre el proyecto pedagógico y la práctica del docente, a partir de la reconstrucción realizada; con la intención de que esta sea útil para la elaboración de nuevos proyectos de educación física en básica primaria.

La synthese d'acides [β-amino α-hydroxy] benzenebutyrique et [amino-3 hydroxy-2 methyl-5] caproique a partir des α-aminoaldehydes correspondants est etudiee

5′-N-(α-Amino-β-mercaptoacyl)amino-5′-deoxynucleosides have been synthesized by coupling of N-formylthiazolidines derived from D- and L-penicillamine, and D- and L-cysteine to 5′-amino-5′-deoxynucleosides using the DCC/HOSu method, followed by deprotection in N HCL in MeOH under argon. Although these compounds were designed as potential anti-HIV-1 agents, none of them showed anti-HIV-1 activity in MT-4 cells or antiviral effect against some other viruses, at concentrations below the cytotoxicity threshold. 5′-N-(α-Amino-β-mercaptoacyl)amino-5′-desoxynucleoside als potentiell antivirale Verbindungen 5′-N-(α-Amino-β-mercaptoacyl)amino-5′-desoxynucleoside wurden durch Kopplung von N-Formylthiazolidinen (aus D- und L-Penicillamin bzw. D-und L-Cystein) mit den entspr. 5′-Amino-5′-desoxynucleosiden mittels DCC/HOSu Methode und anschliesender Entfemung der Schutzgruppe mit N HCL in MeOH unter Argon hergestellt. Diese Verbindungen wurden als potentielle anti-HIV-1 Agentien entwickelt, zeigen aber unter der Cytotoxizitats-Schwelle keine anti-HIV-1 Wirkung gegenuber MT-4-Zellen oder anderen Viren.

Synthese par addition chimique de cyano stannane de tributyle avec des phenylalaninal ou leucinal N proteges

Analogues of the potent anti-influenza A and B compound, 4-guanidino-Neu5Ac2en, are described in which the stereochemically demanding C-6-glycerol side-chain is truncated. Syntheses of the one- and two-carbon side-chain analogues, of both 4-guanidino- and 4-amino-Neu5Ac2en, are presented, as well as the syntheses of analogues lacking any side-chain. Whilst complete removal of the C-6 side-chain abolishes activity, a stepwise increase in inhibition of influenza neuraminidase and influenza A and B in cell culture with increasing C-6 chain length is observed. The one-carbon, hydroxymethyl derivative retains significant activity to represent a suitable lead in the search for neuraminidase inhibitors of reduced stereochemical demand and synthetic complexity.

Synthese par addition chimique de cyano stannane de tributyle avec des phenylalaninal ou leucinal N proteges

The nucleoside antibiotic ascamycin [2-chloro-5'- O -[ N -( L-alanyl )sulfamoyl] adenosine 1 ] has been synthesized by an improved procedure involving the direct condensation of 2-chloro-2',3'- O -isopropylidene-5'- O -sulfamoyladenosine ( 3 ) with Boc- L -Ala-OSu in DMF and in the presence of DBU, followed by removal of the protecting groups. A similar condensation of 3 with Boc- D -Ala-OSu and Boc-Gly-OSu, and subsequent deprotection, yielded the D -Ala and Gly analogues of 1 , namely 2-chloro-5'- O -[ N -( D -alanyl)sulfamoyl] and 2-chloro-5'- O -[ N -(glycyl)sulfamoyl]adenosine [ D -ascamycin ( 14 ) and (18)]. Similar reactions of 2',3'- O -isopropylidene-5'- O -sulfamoyladenosine, 6 with the three amino acid derivatives above mentioned provided the corresponding adenosine analogues 12 , 16 and 20 . Several studies directed to demonstrate that the previous protection of the 6-NH2 group of the adenosine derivatives 3 and 6 is not necessary for the selective aminoacylation of the SO2NH2 group are also reported.

This report concerns the sentence-picture matching behavior of 100 neurologically healthy and 169 brain-damaged subjects, all of whom were unilingual adult right-handers. Within this population, 144 subjects were totally unschooled illiterates and the remaining 125 had received school education and thereafter had retained writing skills and reading habits. Brain-damaged subjects were tested less than 2 months after a first left- or right-hemisphere stroke. All subjects were administered an aphasia screening battery including, among other subtests, a set of six sentence-picture matching stimuli. For each of these six stimuli, subjects heard a sentence uttered by the examiner and were then requested to match this sentence with one of four drawings presented within a single display divided into four quadrants of equal surface. Three sentences were syntactically “simple” (noun subject + verb) and three were relatively more “complex” (noun subject + verb + one or two noun complements). Evidence of unilateral neglect was found in both left- and right-brain-damaged illiterates and literates. Moreover, the right neglect of left-brain-damaged subjects was manifest mostly when target sentences were relatively “complex” whereas the left neglect of right-brain-damaged subjects was manifest irrespective of the syntactic complexity of target sentences. Our data are interpreted as indicative of an interaction between two cognitive disorders resulting from dysfunctions of asymmetrically represented cognitive mechanisms. The implications of these findings with respect to clinical and research aphasia testing are discussed.

Four analogues of ascamycin 〈5′-O-[N-(L-alanyl)sulfamoyl]-2-chloroadenosine〉 (1) in which the 2-chloroadenosine moiety has been replaced by uridine, thymidine, cytidine, and 2′-deoxy-5-methylcytidine have been synthesized by selective aminoacylation of the 5′-O-sulfamoyl derivatives 2, 9, 14, and 21 of 2′,3′-di-O-acetyluridine, 3′-O-acetylthymidine, 2′,3′-O-isopropylidenecytidine, and 3′-O-acetyl-2′-deoxy-5-methylcytidine, respectively, with Boc-L-Ala-OSu in DMF and in the presence of DBU, followed by removal of the protecting groups. Similarly, 5′-O-[N-(D-alanyl)sulfamoyl]uridine (8) has been prepared from Boc-D-Ala-OSu and 2. Compounds 14 and 21 were directly prepared by sulfamoylation of the 4-N-(dimethylamino)methylene derivatives 13 and 20 of 2′,3′-O-isopropylidenecytidine and 3′-O-acetyl-2′-deoxy-5-methylcytidine, respectively, via the intermediate 5′-O-tributyltin derivatives. Compound 20 was obtained from 5′-O-(tert-butyldimethylsilyl)thymidine (17) by a route involving acetylation, conversion of the thymidine moiety into 5-methylcytosine through the corresponding triazolylpyrimidinone, and amidine protection. Synthese von Pyrimidin-Analoga des Nucleosid-Antibiotikums Ascamycin Vier Analoga des Ascamycins 〈5′-O′-O-[N-(L-alanyl)sulfamoyl]-2-chloradenosin〉(1), bei welchen der 2-Chloradenosinrest durch Uridin, Thymidin, Cytidin und 2′-Deoxy-5-methylcytidin ersetzt wurde, sind durch selektive Aminoacylierung der 5′-O-Sulfamoyl-Derivate 2, 9, 14 und 21 des 2′,3′-Di-O-acetyluridins, 3′-O-Acetylthymidins, 2′,3′-O-Isopropylidencytidins, bzw. des 3′-O-Acetyl-2′-deoxy-5-methylcytidins mit Boc-L-Ala-OSu in DMF und in Anwesenheit von DBU, mit nachfolgender Abspaltung der Schutzgruppen, erhalten worden. Ahnlich wurde 5′-O-[N-(D-Alanyl)sulfamoyl]uridin (8) ausgehend von Boc-D-Ala-OSu und 2 hergestellt. Die Verbindungen 14 und 21 wurden direkt durch Sulfamoylierung der 4-N-(Dimethylamino)methylen-Derivate 13 und 20 von 2′,3′-O-Isopropylidencytidin bzw. 3′-O-Acetyl-2′-deoxy-5-methylcytidin uber die 5′-O-Tributylzinn-Zwischenverbindungen dargestellt. Verbindung 20 wurde aus 5′-O-Isopropylidencytidin bzw. 3′-O-Acetyl-2′-deoxy-5-methylcytidin uber die 5′-O-Tributylzinn-Zwischenverbindungen dargestellt. Verbindung 20 wurde aus 5′-O-(tert-Bu-tyldimethylsilyl)thymidin (17) mittels Acetylierung und nachfolgende Uberfuhrung des Thymidinrestes in 5-Methylcytosin uber das entsprechende Triazolylpyrimidinon unter Schutz der Amidingruppe erhalten.

One hundred neurologically healthy adults were tested for their pointing (choosing one of four or six line drawings as the match to an auditorily presented linguistic stimulus), naming (from line drawings), and repetition abilities. All subjects were unilingual adult right-handers. Fifty-seven subjects were totally unschooled illiterates and 43 were fluent readers. Statistically significant differences were found to exist between the scores of the illiterate and literate subpopulations across all tasks. With the focus being placed on these cultural differences, the discussion bears on: (a) the interaction between linguistic and iconographic factors in certain types of naming and pointing tasks currently used in clinical and research aphasiology, (b) some of the linguistic parameters which are apparently at stake in repetition behavior, and (c) the circumstances in which aphasiological research dealing with groups of patients cannot yield reliable data without reference to neurologically healthy controls. It is argued that, when testing brain-damaged patients of different cultural backgrounds, one runs the risk of over- or underestimating the frequency of aphasia if one does not refer to norms which explicitly take educational level into account.

This report bears on the behavior of 188 unilateral stroke subjects when administered an aphasia screening test comprising a short interview as well as naming, repetition, word-picture matching and sentence-picture matching tasks. All subjects were unilingual lusophone adult (40 yr of age or older) right-handers. Furthermore, they were either totally unschooled illiterates or they had received school education and thereafter retained writing skills and reading habits. Subjects were tested less than 2 months after a first unilateral stroke. In all tasks, global error scores were greater among left and right brain-damaged illiterate and literate subjects than among their controls. In repetition and matching, these differences were statistically significant for the left but not for the right-stroke groups, irrespective of the literacy factor. In naming, on the other hand, significant differences were found not only for the two left-stroke groups but also for the right-stroke illiterate group although not for the right-stroke literate one. Likewise, some degree of word-finding difficulty and of reduction in speech output as well as sizeable production of phonemic paraphasias were observed in the interviews of several right-stroke illiterates, clearly less in those of right-stroke literates. These findings lead us to suggest that cerebral representation of language is more ambilateral in illiterates than it is in school educated subjects although left cerebral "dominance" remains the rule in both.

Objetivos: Determinar la actividad larvicida de la hormona reguladora de crecimiento metopreno. Diseño: Estudio experimental. Lugares: Instituto de Investigación de Ciencias Biológicas Antonio Raimondi, Facultad de Ciencias Biológicas, Universidad Nacional Mayor de San Marcos. Sub-Región de Salud de Madre de Dios. Centro de Investigación Biológica para el Desarrollo Amazónico. Material biológico: Larvas de Aedes aegypti en estadios III y IV. Intervenciones: Se realizó 3 bioensayos de laboratorio para evaluar la actividad larvicida de la hormona reguladora de crecimiento metopreno (Altosid)® sobre 7 000 larvas de Aedes aegypti, en los estadios III y IV, a nivel de laboratorio y sobre criaderos naturales de Anopheles benarrochi. La población larval se obtuvo de los criaderos ubicados en las comunidades de La Cachuela, La Joya y Las Piedras, situadas en la provincia de Tambopata (Puerto Maldonado), departamento de Madre de Dios. La actividad larvicida se determinó con 2 dosis del metopreno, 0,004 y 0,008 g/L. Se realizó los bioensayos por triplicado, utilizando agua de criadero. Para determinar la eficacia y susceptibilidad, se hizo lecturas a las 24, 48, 72 y 96 horas después del tratamiento. Principales medidas de resultados: Actividad larvicida del metopreno. Resultados: Se obtuvo una mortalidad de 85,2% y 92%, para las diluciones de 0,004 y 0,008 g/L, en el laboratorio y en los criaderos naturales, respectivamente. La dosis letal media (DL50) fue 0,0018, 0,0014, 0,0017 y 0,0012 g/L, a las 24, 48, 72 y 96 horas, respectivamente. La aplicación sobre los criaderos se realizó con la dosis de 0,008 g/L de metopreno, obteniéndose una DL50 de 0,0056, 0,0048, 0,0034 y 0,0025 g/L a las 24, 48, 72 y 96 horas, respectivamente. La DL90 fue de 0,0098, 0,0086 g/L, 0,008 g/L y 0,0070 g/L, a las 24, 48, 72 y 96 horas, respectivamente, obteniéndose a las 96 horas 100% de mortalidad. Conclusiones: La máxima efectividad del metopreno fue con la dosis 0,008 g/L y a las 96 horas., Objectives: To determine growth regulating hormone methoprene larvicide's activity. Design: Experimental study. Setting: Instituto de Investigacion de Ciencias Biologicas Antonio Raimondi, Facultad de Ciencias Biologicas, Universidad Nacional Mayor de San Marcos. Sub-Region de Salud de Madre de Dios. Centro de Investigacion Biologica para el Desarrollo Amazonico. Biologic material: Stages III and IV Aedes aegypti larves. Interventions: Three laboratory bioessays were done to determine regulating hormone methoprene (Altosid)® on 7 000 stages III and IV Aedes aegypti larves, in the laboratory and in Anopheles benarrochi natural breeding places. Larval population was obtained from breeding places located in La Cachuela, La Joya and Las Piedras communities, Tambopata province (Puerto Maldonado), Madre de Dios department. Larvicide activity was determined by 2 methoprene doses, 0,004 and 0,008 g/L. Bioessays were done by triplicate using breeding places water. Readings at 24, 48, 72 and 96 hours following treatment were done to determine both efficacy and susceptibility. Main outcome measures: Methoprene larvicide activity. Results: Mortality of 85,2% and 92% was obtained for 0,004 and 0,008 g/L dilutions, both at the laboratory and natural breeding places. Median lethal doses (LD50) were 0,0018, 0,0014, 0,0017 and 0,0012 g/L, at 24, 48, 72 y 96 hours respectively. Application on breeding places was done with 0,008 g/L methoprene dosis obtaining 0,0056, 0,0048, 0,0034 and 0,0025 g/L LD50 at 24, 48, 72 y 96 hours, respectively. LD90 was 0,0098, 0,0086 g/L, 0,008 g/L and 0,0070 g/L, at 24, 48, 72 and 96 hours respectively, obtaining 100% mortality at 96 hours. Conclusions: Maximum effectiveness was obtained with methoprene 0,008 g/L dose at 96 hours.

La linguatulosis es una zoonosis causada por Linguatula serrata, parásito que puede afectar al hombre en su estadio ninfal y adulto, siendo los principales mecanismos de transmisión el contacto con el perro doméstico y la ingesta de vísceras infectadas mal cocidas de bovinos. El presente estudio tuvo como objetivo determinar la prevalencia, abundancia e intensidad media del estadio ninfal de L. serrata en ganglios linfáticos mesentéricos yeyuno-iliacos de reses beneficiadas en dos camales de la ciudad de Lima, Perú, procedentes de los departamentos de Puno, Junín, La Libertad, Amazonas, Pasco y Lima. Se recolectaron 3576 ganglios de 368 animales, se les retiró la grasa circundante y refrigeraron a 5 °C hasta su procesamiento. Se realizaron cortes longitudinales en ganglios con microabscesos, granulomas calcificados o con nódulos de color amarillo, verde o gris. Las ninfas colectadas fueron fijadas y montadas. Resultados de la morfometría de las ninfas indicaron promedios de 4.95 mm de largo total, 1.39 mm de ancho anterior y 0.76 mm de ancho posterior. La prevalencia de infección por ninfas de L. serrata fue de 5.97%, siendo más frecuente en animales de 4-5 años de edad. El ganado más afectado procedía de Chachapoyas, Amazonas (13/121) y de Huancayo, Junín (6/70). La abundancia media fue de 0.14 (0-2) y la intensidad media de 2.5 (2-3)., Linguatulosis is a zoonosis caused by Linguatula serrata. The nymph and adult stages of the parasite can affect humans, and the man main mechanisms of transmission is through contact with domestic dogs and ingestion of uncooked infected cattle viscera. This study aimed to determine the prevalence, mean abundance, and the mean intensity of the nymphal stage ofL. serrata in mesenteric lymph nodes of cattle slaughtered in two abattoirs in Lima, Peru. The animals were brought from the departments of Puno, Junín, La Libertad, Amazonas, Pasco and Lima. A total of 3576 lymph nodes from 368 cattle were collected, fat was removed and stored at 5 °C. Nodes with micro abscesses, calcified granulomas and yellow, green or gray nodules were selected and longitudinal cuts were done. Nymphs were fixed and mounted for evaluation. Results of the morphometry showed averages of 4.95 mm total length, 1.39 mm anterior width and 0.76 mm posterior width. The prevalence of infection by nymphs ofL. serrata was 5.97%, especially in 4-5 years old animals. The most frequent affected cattle were from Chachapoyas, Amazonas (13/121) and Huancayo, Junín (6/70). The mean abundance was 0.14 (0-2) and the mean intensity was 2.5 (2-3).

En el presente trabajo se comparó la actividad parasitoide de las microavispas Spalangia endius y Muscidifurax sp. sobre el estadio pupal de Musca domestica. La mejor temperatura para la crianza fue de 25 °C. El ciclo de S. endius se completó en 22,6 días, mientras en Muscidifurax sp. en 14,8 días. La duración del ciclo fue inversamente relacionada con la temperatura, siendo mayor en las hembras que en los machos. La longevidad fue similar en ambas especies de microavispas (20,7 días en S. endius y 18,6 días en Muscifurax sp.).La oviposicion de S. endius a los 15 días fue sobre 175 pupas de M. domestica, valor mayor que Muscidifurax que parasitó 140 pupas en 16 días. En ambas especies la mayor postura ocurrió al tercer día. Las pupas de M. domestica de dos días de maduración fueron las mas parasitadas con 66,4% de parasitismo efectivo por S. endius y 60,2% por Muscidifurax sp. El número óptimo de pupas de M. domestica fue 10 (10:1). Se concluye que en condiciones de laboratorio, Spalangia endius puede ser un eficiente controlador biológico de pupas de Musca domestica. In this work we compared the parasitoid activity of the microhymenopterans Spalangia endius and Muscidifurax sp. on the pupae of Musca domestica. The better temperature for the reared was of 25 °C. The cycle of S. endius was completed in 22,6 days, while in Muscidifurax sp. in 14,8 days. The cycle duration was inversely related to temperature, in the females was highest than males. The longevity was similar in both microhymenopterans species (20,7 days in S. endius and 18,6 days in Muscifurax sp.). Spalangia endius oviposited on 175 pupae of M. domestica in 15 days; this value was highest than Muscidifurax that oviposited 140 pupae in 16 days. In both species the highest posture occurred in the third day. Musca domestica pupae with two maturation days were the more parasited; S. endius with 66,4% and Muscidifurax sp. with 60,2% of effective parasitism. The better number of M. domestica pupae was 10 (10:1). We conclude that under laboratory conditions, S. endius can be an efficient biological controller of pustules of M. domestica.

Boron trifluoride-diethyl ether mediated addition of trimethylsilylcyanide (TMSCN) to the chiral acetals derived from Z-L- and Z-D-phenyl alaninal, (Z=N-benzyloxycarbonyl), and (+)-(2S,4S)- and (–)-(2R,4R)-2,4-pentanediol stereoselectively gave the four stereoisomers of the 3-amino-2-hydroxy-4-phenylbutanoic acid, key intermediates for bestatin and bestatin analogues.