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1.
Chemistry ; 7(6): 1165-70, 2001 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-11322541

RESUMEN

A copper-mediated procedure for terminal alkynyl-propargyl coupling has been applied to "skipped" bis-terminal undecatetrayne and 1,4-bis(pseudo)halobut-2-ynes with the aim of preparing ring carbomers of representative strained and loose cycloalkanes, namely [N]pericyclynes. Two unprecedented, cyclic. "skipped" polyynes with CH2 vertices have been isolated as mixtures of diastereoisomers: an isomer 1b and a dimer 2a of [5]pericyclyne 1a. The isomer 1b is a cyclotetrayne with an exocyclic allene function resulting from a unique formal SN process. Its structure has been established by 1H/13C HMQC and HMBC two-dimensional NMR analysis. According to density functional theory calculations, it is about 6 kcalmol(-1) more stable than [5]pericyclyne (1a). Compound 1b can also be regarded as a C13-relaxed [4]pericyclyne, a long sought "skipped" C12 tetrayne. The dimer 2a is a C30 ring that results from a formal SN process. It is a stable ring carbomer of cyclodecane, that is, a [10]pericyclyne, with four CH2 vertices.

2.
J Econ Entomol ; 92(1): 104-9, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10036984

RESUMEN

Fruit bins infested with diapausing larvae of codling moth larvae, Cydia pomonella (L.), are a source of reinfestation of orchards and may jeopardize the success of mating disruption programs and other control strategies. Bins are not routinely treated for control of overwintering codling moth before placing them in orchards. Entomopathogenic nematodes provide a noninsecticidal alternative to methyl bromide that could be applied at the time bins are submerged in dump tanks at the packing house for flotation of fruit. Diapausing codling moth larvae in miniature fruit bins were highly susceptible to infective juveniles of Steinernema carpocapsae (Weiser). Immersion of bins in suspensions of S. carpocapsae ranging from 5 to 100 infective juveniles per milliliter of water resulted in 68-100% mortality. Immersion times of 1 or 5 min in suspensions with 5 infective juveniles of S. carpocapsae per milliliter of water, with and without Tween 80 (0.01%), yielded essentially the same mortality of codling moth larvae. Highest mortalities in codling moth larvae (88%) after treatment of bins in suspensions of 5 infective juveniles of S. carpocapsae per milliliter of water were observed after incubation for 24 h at 25 degrees C and 70% RH. Lowest mortalities (37%) were observed after incubation at 15 degrees C and 35% RH. Comparative tests conducted with Heterorhabditis marelatus Liu & Berry, Steinernema kraussei (Steiner), and S. carpocapsae with 5 infective juveniles per milliliter of water resulted in 21.7, 53.9, and 68.7% mortality, respectively. The use of miniature fruit bins as described in this article provides an effective means of assessing nematode efficacy without the cumbersome size of commercial bins.


Asunto(s)
Mariposas Nocturnas/parasitología , Control Biológico de Vectores/métodos , Rhabditoidea , Animales
3.
Horm Metab Res ; 21(10): 553-7, 1989 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2807145

RESUMEN

The kinetics of abdomen, haemolymph and thoracic-muscle steroid and phospholipid concentrations have been determined in adult worker-bees kept for 0 to 12 hrs starving in darkness, either grouped by 8 (controls) or strictly isolated, or isolated in presence of a piece of cotton impregnated with 1 microgram azelaic acid and 1 microgram pimelic acid, the so-called "survivones" which restore the lifespan of isolated bees. The dynamics of both steroids and phospholipids strongly deviates in isolated bees relatively to controls. The introduction of survivones completely restored the variations of haemolymph steroids of haemolymph and thorax phospholipids of isolated bees to exactly similar features as in controls. The action of the lipoic hormones "survivones" thus involves the participation of lipid metabolism.


Asunto(s)
Abejas/efectos de los fármacos , Hormonas de Insectos/farmacología , Fosfolípidos/metabolismo , Aislamiento Social/psicología , Esteroides/metabolismo , Abdomen , Animales , Abejas/metabolismo , Ácidos Dicarboxílicos/farmacología , Hemolinfa/metabolismo , Músculos/metabolismo , Ácidos Pimélicos/farmacología , Estrés Psicológico/metabolismo , Tórax/metabolismo
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