Banca de DEFESA: ANALÚ CAMPOS REIS

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : ANALÚ CAMPOS REIS
DATE: 23/06/2023
TIME: 08:00
LOCAL: Google meet
TITLE:

 

 

Identification and synthesis of semiochemicals involved in the communication of Atheloca subrufella (Hulst) (Lepidoptera: Phycitidae) and Anthonomus grandis Boheman (Coleoptera: Curculionidae)

KEY WORDS:

 semiochemicals, pheromone synthesis, pest control

PAGES: 109
BIG AREA: Ciências Exatas e da Terra
AREA: Química
SUBÁREA: Química Orgânica
SPECIALTY: Química dos Produtos Naturais
SUMMARY:

Brazil is a country with a large agricultural production and is very diversified, but among
the major economically relevant crops are cotton and Arecaceae. Insect pests are increasingly
important for cultivation, especially in large areas of homogeneous plantations such as
Arecaceae and cotton, causing a reduction in productivity. The Anthonomus grandis Boheman
(Coleoptera: Curculionidae), known as cotton weevil, in its larval stage, develops inside the
flower buds, leading to losses in the cotton crop. This reduction in productivity is observed and
gradually increases if severe control measures are not taken. Atheloca subrufella (Hulst)
(Lepidoptera: Phycitidae), known as the coconut moth, causes damage to the plant when in
the larval stage, it feeds on the fruit's mesocarp, preventing the flow of sap, and causing it to fall
prematurely, thus reducing the productivity of the coconut tree. The use of sprays with
insecticides to control these pests is not efficient, since they lodge mainly inside the plant/fruit
and insecticides are not able to reach them and are not recommended. Semiochemicals are
presented as an efficient and sustainable control method. Thus, this work aimed to synthesize
the semiochemicals of these insects.A. grandis already has its pheromonal mixture identified
and in commercial use, consisting of four compounds:(+)-cis-2-isopropenyl-1-methyl-
cyclobutane-ethanol (Grandisol); (Z)-3,3-dimethylcyclohexylidene-ethanol (Grandlure II); (E)-
3,3-dimethylcyclohexylideneacetaldehyde (GrandlureIII);and(Z)-3,3-
dimethylcyclohexylidene-acetaldehyde (GrandlureIV). Grandlures II, III and IV were obtained
by a single synthetic route, in just three steps, through an α,β-unsaturated intermediate, [(E,Z)-
ethyl-2-(3,3-dimethylcyclohexylidene)], formed by the Horner-Wadsworth-Emmons reaction.
The alcohol was obtained through reduction with lithium aluminium hydride and the aldehydes,
from the oxidation of the alcohol with PCC, with an overall yield of 82.4%. In the study of the
Chemical Ecology of A. subrufella, two compounds produced by females were identified that
showed activity in the CG-EAD in front of male antennae. Through GC-MS analysis these
compounds were proposed as 6,9-dimethyltetradecane and 6,10-dimethylhexadecane. 13-
methylheptacosane was indicated as the major component in the cuticular extracts of female A.
subrufella. For the synthesis of this molecule, a route containing seven steps was proposed,
using Grignard reactions as a strategy for elongating the carbon chain and inserting the branch
at position 13, obtaining an overall yield of 4.26% in seven steps. The proposed routes proved
to be effective for obtaining the five target molecules.

BANKING MEMBERS:
Presidente - 1119939 - ANTONIO EUZEBIO GOULART SANTANA
Interno(a) - 2272670 - ALINE CAVALCANTI DE QUEIROZ
Interno(a) - 1247925 - ANIELLE CHRISTINE ALMEIDA SILVA
Externo(a) ao Programa - 2149347 - HENRIQUE FONSECA GOULART
Externo(a) à Instituição - DANIELA MARIA DO AMARAL FERRAZ NAVARRO - UFPE
Externo(a) à Instituição - JOHNNATAN DUARTE DE FREITAS - IFAL