90 research outputs found
Biodegradation of nonionic surfactants based on PEG in Pseudomonas mendocina VKM B-1729
Degradation of nonionic surfactants - acyl and alkyl derivatives of PEG - in bacterial cells of Pseudomonas mendocina VKM-1729 was studied. The key step of conversion of the compounds tested was their cleavage into hydrophobic and PEG (PEG) moieties. Aliphatic moieties of detergents were utilized by the bacteria; PEG was accumulated in the environment and then transformed into carboxy derivatives. Cleavage of acyl-PEG resulted from hydrolysis mediated by lipases and produced a fatty acid. An aliphatic aldehyde was a hydrophobic intermediate of cleavage of alkyl-PEG, and the reaction obviously included an oxidation step
ΠΠ»Π°ΡΡΠΈΡΠΈΠΊΠ°ΡΠΈΡ ΠΏΠΎΡΠ»Π΅Π΄ΠΎΠ²Π°ΡΠ΅Π»ΡΠ½ΠΎΡΡΠ΅ΠΉ Π½Π° ΠΎΡΠ½ΠΎΠ²Π΅ ΠΊΠΎΡΠΎΡΠΊΠΈΡ ΠΌΠΎΡΠΈΠ²ΠΎΠ²
Sequence classification problems often arise in such areas as bioinformatics and natural language processing. In the last few year best results in this field were achieved by the deep learning methods, especially by architectures based on recurrent neural networks (RNN). However, the common problem of such models is a lack of interpretability, i.e., extraction of key features from data that affect the most the modelβs decision. Meanwhile, using of less complicated neural network leads to decreasing predictive performance thus limiting usage of state-of-art machine learning methods in many subject areas. In this work we propose a novel interpretable deep learning architecture based on extraction of principal sets of short substrings β sequence motifs. The presence of extracted motif in the input sequence is a marker for a certain class. The key component of proposed solution is differential alignment algorithm developed by us, which provides a smooth analog of classical string comparison methods such as Levenshtein edit distance, and SmithβWaterman local alignment. Unlike previous works devoted to the motif based classification, which used CNN for shift-invariant searching, ours model provide a way to shift and gap invariant extraction of motifs.ΠΠ°Π΄Π°ΡΠΈ, ΡΠ²ΡΠ·Π°Π½Π½ΡΠ΅ Ρ ΠΊΠ»Π°ΡΡΠΈΡΠΈΠΊΠ°ΡΠΈΠ΅ΠΉ ΠΏΠΎΡΠ»Π΅Π΄ΠΎΠ²Π°ΡΠ΅Π»ΡΠ½ΠΎΡΡΠ΅ΠΉ ΡΠΈΠΌΠ²ΠΎΠ»ΠΎΠ² Π½Π΅ΠΊΠΎΡΠΎΡΠΎΠ³ΠΎ Π°Π»ΡΠ°Π²ΠΈΡΠ°, ΡΠ°ΡΡΠΎ Π²ΠΎΠ·Π½ΠΈΠΊΠ°ΡΡ Π² ΡΠ°ΠΊΠΈΡ
ΠΎΠ±Π»Π°ΡΡΡΡ
, ΠΊΠ°ΠΊ Π±ΠΈΠΎΠΈΠ½ΡΠΎΡΠΌΠ°ΡΠΈΠΊΠ° ΠΈ ΠΎΠ±ΡΠ°Π±ΠΎΡΠΊΠ° Π΅ΡΡΠ΅ΡΡΠ²Π΅Π½Π½ΠΎΠ³ΠΎ ΡΠ·ΡΠΊΠ°. ΠΠ΅ΡΠΎΠ΄Ρ Π³Π»ΡΠ±ΠΎΠΊΠΎΠ³ΠΎ ΠΎΠ±ΡΡΠ΅Π½ΠΈΡ, Π² ΠΎΡΠΎΠ±Π΅Π½Π½ΠΎΡΡΠΈ ΠΌΠΎΠ΄Π΅Π»ΠΈ Π½Π° ΠΎΡΠ½ΠΎΠ²Π΅ ΡΠ΅ΠΊΡΡΡΠ΅Π½ΡΠ½ΡΡ
Π½Π΅ΠΉΡΠΎΠ½Π½ΡΡ
ΡΠ΅ΡΠ΅ΠΉ, Π² ΠΏΠΎΡΠ»Π΅Π΄Π½ΠΈΠ΅ Π½Π΅ΡΠΊΠΎΠ»ΡΠΊΠΎ Π»Π΅Ρ Π·Π°ΡΠ΅ΠΊΠΎΠΌΠ΅Π½Π΄ΠΎΠ²Π°Π»ΠΈ ΡΠ΅Π±Ρ ΠΊΠ°ΠΊ Π½Π°ΠΈΠ±ΠΎΠ»Π΅Π΅ ΡΡΡΠ΅ΠΊΡΠΈΠ²Π½ΡΠΉ ΡΠΏΠΎΡΠΎΠ± ΡΠ΅ΡΠ΅Π½ΠΈΡ ΠΏΠΎΠ΄ΠΎΠ±Π½ΡΡ
Π·Π°Π΄Π°Ρ. ΠΠ΄Π½Π°ΠΊΠΎ ΡΡΡΠ΅ΡΡΠ²ΡΡΡΠΈΠ΅ ΠΏΠΎΠ΄Ρ
ΠΎΠ΄Ρ ΠΈΠΌΠ΅ΡΡ ΡΠ΅ΡΡΠ΅Π·Π½ΡΠΉ Π½Π΅Π΄ΠΎΡΡΠ°ΡΠΎΠΊ β Π½ΠΈΠ·ΠΊΡΡ ΠΈΠ½ΡΠ΅ΡΠΏΡΠ΅ΡΠΈΡΡΠ΅ΠΌΠΎΡΡΡ ΠΏΠΎΠ»ΡΡΠ°Π΅ΠΌΡΡ
ΡΠ΅Π·ΡΠ»ΡΡΠ°ΡΠΎΠ². ΠΡΠ°ΠΉΠ½Π΅ ΡΠ»ΠΎΠΆΠ½ΠΎ ΡΡΡΠ°Π½ΠΎΠ²ΠΈΡΡ ΠΊΠ°ΠΊΠΈΠ΅ ΠΈΠΌΠ΅Π½Π½ΠΎ ΡΠ²ΠΎΠΉΡΡΠ²Π° Π²Ρ
ΠΎΠ΄Π½ΠΎΠΉ ΠΏΠΎΡΠ»Π΅Π΄ΠΎΠ²Π°ΡΠ΅Π»ΡΠ½ΠΎΡΡΠΈ ΠΎΡΠ²Π΅ΡΡΡΠ²Π΅Π½Π½Ρ Π·Π° Π΅Ρ ΠΏΡΠΈΠ½Π°Π΄Π»Π΅ΠΆΠ½ΠΎΡΡΡ ΠΊ ΡΠΎΠΌΡ ΠΈΠ»ΠΈ ΠΈΠ½ΠΎΠΌΡ ΠΊΠ»Π°ΡΡΡ. Π£ΠΏΡΠΎΡΠ΅Π½ΠΈΠ΅ ΠΆΠ΅ ΡΠ°ΠΊΠΈΡ
ΠΌΠΎΠ΄Π΅Π»Π΅ΠΉ Ρ ΡΠ΅Π»ΡΡ ΠΏΠΎΠ²ΡΡΠ΅Π½ΠΈΡ ΠΈΡ
ΠΈΠ½ΡΠ΅ΡΠΏΡΠ΅ΡΠΈΡΡΠ΅ΠΌΠΎΡΡΠΈ, Π² ΡΠ²ΠΎΡ ΠΎΡΠ΅ΡΠ΅Π΄Ρ, ΠΏΡΠΈΠ²ΠΎΠ΄ΠΈΡ ΠΊ ΡΠ½ΠΈΠΆΠ΅Π½ΠΈΡ ΠΊΠ°ΡΠ΅ΡΡΠ²Π° ΠΊΠ»Π°ΡΡΠΈΡΠΈΠΊΠ°ΡΠΈΠΈ. Π’Π°ΠΊΠΈΠ΅ Π½Π΅Π΄ΠΎΡΡΠ°ΡΠΊΠΈ ΠΎΠ³ΡΠ°Π½ΠΈΡΠΈΠ²Π°ΡΡ ΠΏΡΠΈΠΌΠ΅Π½Π΅Π½ΠΈΠ΅ ΡΠΎΠ²ΡΠ΅ΠΌΠ΅Π½Π½ΡΡ
ΠΌΠ΅ΡΠΎΠ΄ΠΎΠ² ΠΌΠ°ΡΠΈΠ½Π½ΠΎΠ³ΠΎ ΠΎΠ±ΡΡΠ΅Π½ΠΈΡ Π²ΠΎ ΠΌΠ½ΠΎΠ³ΠΈΡ
ΠΏΡΠ΅Π΄ΠΌΠ΅ΡΠ½ΡΡ
ΠΎΠ±Π»Π°ΡΡΡΡ
. Π Π½Π°ΡΡΠΎΡΡΠ΅ΠΉ ΡΠ°Π±ΠΎΡΠ΅ ΠΌΡ ΠΏΡΠ΅Π΄ΡΡΠ°Π²Π»ΡΠ΅ΠΌ ΠΏΡΠΈΠ½ΡΠΈΠΏΠΈΠ°Π»ΡΠ½ΠΎ Π½ΠΎΠ²ΡΡ, ΠΈΠ½ΡΠ΅ΡΠΏΡΠ΅ΡΠΈΡΡΠ΅ΠΌΡΡ Π°ΡΡ
ΠΈΡΠ΅ΠΊΡΡΡΡ Π½Π΅ΠΉΡΠΎΠ½Π½ΡΡ
ΡΠ΅ΡΠ΅ΠΉ, ΠΎΡΠ½ΠΎΠ²Π°Π½Π½ΡΡ Π½Π° ΠΏΠΎΠΈΡΠΊΠ΅ Π½Π°Π±ΠΎΡΠ° ΠΊΠΎΡΠΎΡΠΊΠΈΡ
ΠΏΠΎΠ΄ΠΏΠΎΡΠ»Π΅Π΄ΠΎΠ²Π°ΡΠ΅Π»ΡΠ½ΠΎΡΡΠ΅ΠΉ β ΠΌΠΎΡΠΈΠ²ΠΎΠ², Π½Π°Π»ΠΈΡΠΈΠ΅ ΠΊΠΎΡΠΎΡΡΡ
Π²Π»ΠΈΡΠ΅Ρ Π½Π° ΠΏΡΠΈΠ½Π°Π΄Π»Π΅ΠΆΠ½ΠΎΡΡΡ ΠΏΠΎΡΠ»Π΅Π΄ΠΎΠ²Π°ΡΠ΅Π»ΡΠ½ΠΎΡΡΠΈ ΠΊ ΠΎΠΏΡΠ΅Π΄Π΅Π»Π΅Π½Π½ΠΎΠΌΡ ΠΊΠ»Π°ΡΡΡ. ΠΠ»ΡΡΠ΅Π²ΠΎΠΉ ΡΠΎΡΡΠ°Π²Π»ΡΡΡΠ΅ΠΉ ΠΏΡΠ΅Π΄Π»Π°Π³Π°Π΅ΠΌΠΎΠ³ΠΎ ΡΠ΅ΡΠ΅Π½ΠΈΡ ΡΠ²Π»ΡΠ΅ΡΡΡ ΡΠ°Π·ΡΠ°Π±ΠΎΡΠ°Π½Π½ΡΠΉ Π½Π°ΠΌΠΈ Π°Π»Π³ΠΎΡΠΈΡΠΌ Π΄ΠΈΡΡΠ΅ΡΠ΅Π½ΡΠΈΡΡΠ΅ΠΌΠΎΠ³ΠΎ Π²ΡΡΠ°Π²Π½ΠΈΠ²Π°Π½ΠΈΡ, ΡΠ²Π»ΡΡΡΠΈΠΉΡΡ Π΄ΠΈΡΡΠ΅ΡΠ΅Π½ΡΠΈΡΡΠ΅ΠΌΡΠΌ Π°Π½Π°Π»ΠΎΠ³ΠΎΠΌ ΡΠ°ΠΊΠΈΡ
ΠΊΠ»Π°ΡΡΠΈΡΠ΅ΡΠΊΠΈΡ
ΡΠΏΠΎΡΠΎΠ±ΠΎΠ² ΡΡΠ°Π²Π½Π΅Π½ΠΈΡ ΡΡΡΠΎΠΊ, ΠΊΠ°ΠΊ ΡΠ΅Π΄Π°ΠΊΡΠΈΠΎΠ½Π½ΠΎΠ΅ ΡΠ°ΡΡΡΠΎΡΠ½ΠΈΠ΅ ΠΠ΅Π²Π΅Π½ΡΡΠ΅ΠΉΠ½Π° ΠΈ Π°Π»Π³ΠΎΡΠΈΡΠΌ Π‘ΠΌΠΈΡΠ°βΠΠ°ΡΠ΅ΡΠΌΠ°Π½Π°. Π ΠΎΡΠ»ΠΈΡΠΈΠ΅ ΠΎΡ ΠΏΡΠ΅Π΄ΡΠ΄ΡΡΠΈΡ
ΡΠ°Π±ΠΎΡ, ΠΏΠΎΡΠ²ΡΡΠ΅Π½Π½ΡΡ
ΠΊΠ»Π°ΡΡΠΈΡΠΈΠΊΠ°ΡΠΈΠΈ ΠΏΠΎΡΠ»Π΅Π΄ΠΎΠ²Π°ΡΠ΅Π»ΡΠ½ΠΎΡΡΠ΅ΠΉ Π½Π° ΠΎΡΠ½ΠΎΠ²Π΅ ΠΌΠΎΡΠΈΠ²ΠΎΠ², Π½ΠΎΠ²ΡΠΉ ΠΌΠ΅ΡΠΎΠ΄ ΠΏΠΎΠ·Π²ΠΎΠ»ΡΠ΅Ρ Π½Π΅ ΡΠΎΠ»ΡΠΊΠΎ Π²ΡΠΏΠΎΠ»Π½ΡΡΡ ΠΏΠΎΠΈΡΠΊ Π² ΠΏΡΠΎΠΈΠ·Π²ΠΎΠ»ΡΠ½ΠΎΠΉ ΡΠ°ΡΡΠΈ ΡΡΡΠΎΠΊΠΈ, Π½ΠΎ ΠΈ ΡΡΠΈΡΡΠ²Π°ΡΡ Π²ΠΎΠ·ΠΌΠΎΠΆΠ½ΡΠ΅ Π²ΡΡΠ°Π²ΠΊΠΈ
Perkov reaction in series of mixed bis(1,1,3-trihydroperfluoropropyl) alkyl phosphites
Mixed bis(1,1,3-trihydroperfluoropropyl) alkyl phosphites react under mild conditions with chloral to simultaneously give stable phosphoranes with a P-C bond and vinyl phosphates. Β© 1983 Plenum Publishing Corporation
Fluoroalkoxy-derivatives of trivalent phosphorus: Synthesis and reactivity
The review surveys and gives a systematic account of the electronic structures, syntheses, and chemical properties of fluoroalkyl derivatives of trivalent phosphorus (phosphites, thiophosphites, and amidophophites). The methods of preparation and reactivities of fluoroalkyl phosphites are compared with those of unsubstituted phosphites. The bibliography includes 420 references. Β© 1996 Russian Academy of Sciences and Turpion Ltd
Pentaalkoxyphosphoranes in the reactions of alkylene(1,1,3-trihydroperfluoropropyl) phosphites with chloral and bromal
For the first time, stable pentaalkoxyspirophosphoranes were isolated in addition to phosphoranes with P-C bond in the reactions of alkylene-(1,1,3-trihydroperfluoropropyl)phosphites with chloral or bromal. Β© 1987 Plenum Publishing Corporation
Π₯ΠΈΡΡΡΠ³ΠΈΡΠ΅ΡΠΊΠΈΠ΅ ΠΌΠ΅ΡΠΎΠ΄Ρ ΡΡΠ°Π±ΠΈΠ»ΠΈΠ·Π°ΡΠΈΠΈ Π³ΡΡΠ΄Π½ΠΎΠΉ ΠΊΠ»Π΅ΡΠΊΠΈ ΠΏΡΠΈ ΠΌΠ½ΠΎΠΆΠ΅ΡΡΠ²Π΅Π½Π½ΡΡ ΠΏΠ΅ΡΠ΅Π»ΠΎΠΌΠ°Ρ ΡΠ΅Π±Π΅Ρ
Closed chest injury occupies one of the leading places among all injuries. Rib fractures can lead to the formation of floating fragments of the chest wall, the βcostal valveβ. With multiple rib fractures, surgical methods of chest stabilization have been used since the beginning of the 20th century, which have become more popular in recent decades. Β Surgical treatment can significantly reduce pain, accelerate the recovery of respiratory function. In turn, a decrease in pain reduces the incidence of pneumonia, the need for mechanical ventilation and tracheostomy, and the period of hospitalization. There are four main surgical methods of treatment: 1) chest traction methods; 2) external fixation devices; 3) methods of permanent internal fixation; 4) plate osteosynthesis. We also separated the group of techniques performed via thoracoscopic access and the technique using biodegradable materials. Surgical options in the treatment of patients with multiple rib fractures have not been exhausted and are likely to improve with advances in technology.Β ΠΠ°ΠΊΡΡΡΠ°Ρ ΡΡΠ°Π²ΠΌΠ° Π³ΡΡΠ΄ΠΈ Π·Π°Π½ΠΈΠΌΠ°Π΅Ρ ΠΎΠ΄Π½ΠΎ ΠΈΠ· Π»ΠΈΠ΄ΠΈΡΡΡΡΠΈΡ
ΠΌΠ΅ΡΡ ΡΡΠ΅Π΄ΠΈ Π²ΡΠ΅Ρ
ΠΏΠΎΠ²ΡΠ΅ΠΆΠ΄Π΅Π½ΠΈΠΉ. ΠΠ΅ΡΠ΅Π»ΠΎΠΌΡ ΡΠ΅Π±Π΅Ρ ΠΌΠΎΠ³ΡΡ ΠΏΡΠΈΠ²ΠΎΠ΄ΠΈΡΡ ΠΊ ΡΠΎΡΠΌΠΈΡΠΎΠ²Π°Π½ΠΈΡ ΡΠ»ΠΎΡΠΈΡΡΡΡΠΈΡ
ΡΡΠ°Π³ΠΌΠ΅Π½ΡΠΎΠ² Π³ΡΡΠ΄Π½ΠΎΠΉ ΡΡΠ΅Π½ΠΊΠΈ β Β«ΡΠ΅Π±Π΅ΡΠ½ΠΎΠΌΡ ΠΊΠ»Π°ΠΏΠ°Π½ΡΒ». ΠΡΠΈ ΠΌΠ½ΠΎΠΆΠ΅ΡΡΠ²Π΅Π½Π½ΡΡ
ΠΏΠ΅ΡΠ΅Π»ΠΎΠΌΠ°Ρ
ΡΠ΅Π±Π΅Ρ Ρ Π½Π°ΡΠ°Π»Π° Π₯Π₯ Π²Π΅ΠΊΠ° ΠΈΡΠΏΠΎΠ»ΡΠ·ΠΎΠ²Π°Π»ΠΈΡΡ Ρ
ΠΈΡΡΡΠ³ΠΈΡΠ΅ΡΠΊΠΈΠ΅ ΠΌΠ΅ΡΠΎΠ΄Ρ ΡΡΠ°Π±ΠΈΠ»ΠΈΠ·Π°ΡΠΈΠΈ Π³ΡΡΠ΄Π½ΠΎΠΉ ΠΊΠ»Π΅ΡΠΊΠΈ, ΠΊΠΎΡΠΎΡΡΠ΅ Π² ΠΏΠΎΡΠ»Π΅Π΄Π½ΠΈΠ΅ Π΄Π΅ΡΡΡΠΈΠ»Π΅ΡΠΈΡ ΡΡΠ°Π»ΠΈ Π±ΠΎΠ»Π΅Π΅ ΠΏΠΎΠΏΡΠ»ΡΡΠ½ΡΠΌΠΈ. Β Π₯ΠΈΡΡΡΠ³ΠΈΡΠ΅ΡΠΊΠΎΠ΅ Π»Π΅ΡΠ΅Π½ΠΈΠ΅ ΠΏΠΎΠ·Π²ΠΎΠ»ΡΠ΅Ρ Π·Π½Π°ΡΠΈΡΠ΅Π»ΡΠ½ΠΎ ΡΠΌΠ΅Π½ΡΡΠΈΡΡ Π±ΠΎΠ»Π΅Π²ΠΎΠΉ ΡΠΈΠ½Π΄ΡΠΎΠΌ, ΡΡΠΊΠΎΡΠΈΡΡ Π²ΠΎΡΡΡΠ°Π½ΠΎΠ²Π»Π΅Π½ΠΈΠ΅ ΡΠ΅ΡΠΏΠΈΡΠ°ΡΠΎΡΠ½ΠΎΠΉ ΡΡΠ½ΠΊΡΠΈΠΈ ΠΈ ΡΠ΅ΠΌ ΡΠ°ΠΌΡΠΌ ΡΠ½ΠΈΠ·ΠΈΡΡ ΡΠ°ΡΡΠΎΡΡ ΡΠ°Π·Π²ΠΈΡΠΈΡ ΠΏΠ½Π΅Π²ΠΌΠΎΠ½ΠΈΠΈ, ΠΏΠΎΡΡΠ΅Π±Π½ΠΎΡΡΡ Π² ΠΈΡΠΊΡΡΡΡΠ²Π΅Π½Π½ΠΎΠΉ Π²Π΅Π½ΡΠΈΠ»ΡΡΠΈΠΈ Π»Π΅Π³ΠΊΠΈΡ
ΠΈ ΡΡΠ°Ρ
Π΅ΠΎΒΡΡΠΎΠΌΠΈΠΈ ΠΈ ΡΠΎΠΊΡΠ°ΡΠΈΡΡ ΠΏΠ΅ΡΠΈΠΎΠ΄ Π½Π°Ρ
ΠΎΠΆΠ΄Π΅Π½ΠΈΡ Π² ΡΡΠ°ΡΠΈΠΎΠ½Π°ΡΠ΅. Π Π°Π·Π»ΠΈΡΠ°ΡΡ ΡΠ΅ΡΡΡΠ΅ ΠΎΡΠ½ΠΎΠ²Π½ΡΠ΅ Ρ
ΠΈΡΡΡΠ³ΠΈΡΠ΅ΡΠΊΠΈΠ΅ ΠΌΠ΅ΡΠΎΠ΄ΠΈΠΊΠΈ Π»Π΅ΡΠ΅Π½ΠΈΡ, ΠΈΡΠΏΠΎΠ»ΡΠ·ΡΡΡΠΈΠ΅: 1) ΡΡΠ°ΠΊΡΠΈΡ Π³ΡΡΠ΄Π½ΠΎΠΉ ΠΊΠ»Π΅ΡΠΊΠΈ; 2) Π°ΠΏΠΏΠ°ΡΠ°ΡΡ Π²Π½Π΅ΡΠ½Π΅ΠΉ ΡΠΈΠΊΡΠ°ΡΠΈΠΈ; 3) ΠΏΠΎΡΡΠΎΡΠ½Π½ΡΡ Π²Π½ΡΡΡΠ΅Π½Π½ΡΡ ΡΠΈΠΊΡΠ°ΡΠΈΡ; 4) Π½Π°ΠΊΠΎΡΡΠ½ΡΠΉ ΠΎΡΡΠ΅ΠΎΡΠΈΠ½ΡΠ΅Π· ΠΏΠ»Π°ΡΡΠΈΠ½Π°ΠΌΠΈ. Π Π΄Π°Π½Π½ΠΎΠΌ ΠΈΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π½ΠΈΠΈ Π±ΡΠ»ΠΈ Π΄ΠΎΠΏΠΎΠ»Π½ΠΈΡΠ΅Π»ΡΠ½ΠΎ Π²ΡΠ΄Π΅Π»Π΅Π½Ρ ΠΌΠ΅ΡΠΎΠ΄ΠΈΠΊΠ°, ΠΎΡΡΡΠ΅ΡΡΠ²Π»ΡΠ΅ΠΌΠ°Ρ ΡΠ΅ΡΠ΅Π· ΡΠΎΡΠ°ΠΊΠΎΡΠΊΠΎΠΏΠΈΡΠ΅ΡΠΊΠΈΠΉ Π΄ΠΎΡΡΡΠΏ, ΠΈ ΠΌΠ΅ΡΠΎΠ΄ΠΈΠΊΠ°, ΠΈΡΠΏΠΎΠ»ΡΠ·ΡΡΡΠ°Ρ Π±ΠΈΠΎΡΠ°Π·Π»Π°Π³Π°Π΅ΠΌΡΠ΅ ΠΌΠ°ΡΠ΅ΡΠΈΠ°Π»Ρ. Π₯ΠΈΡΡΡΠ³ΠΈΡΠ΅ΡΠΊΠΈΠ΅ Π²ΠΎΠ·ΠΌΠΎΠΆΠ½ΠΎΡΡΠΈ Π² Π»Π΅ΡΠ΅Π½ΠΈΠΈ ΠΏΠ°ΡΠΈΠ΅Π½ΡΠΎΠ² ΡΠΎ ΠΌΠ½ΠΎΠΆΠ΅ΡΡΠ²Π΅Π½Π½ΡΠΌΠΈ ΠΏΠ΅ΡΠ΅Π»ΠΎΠΌΠ°ΠΌΠΈ ΡΠ΅Π±Π΅Ρ Π½Π΅ ΠΈΡΡΠ΅ΡΠΏΠ°Π½Ρ ΠΈ, Π²Π΅ΡΠΎΡΡΠ½ΠΎ, Π±ΡΠ΄ΡΡ ΡΠΎΠ²Π΅ΡΡΠ΅Π½ΡΡΠ²ΠΎΠ²Π°ΡΡΡΡ ΠΏΠΎ ΠΌΠ΅ΡΠ΅ Π΄ΠΎΡΡΠΈΠΆΠ΅Π½ΠΈΠΉ Π² ΡΠ΅Ρ
Π½ΠΎΠ»ΠΎΠ³ΠΈΡΠ΅ΡΠΊΠΎΠΉ ΡΡΠ΅ΡΠ΅.
Reactions of triphenyl phosphite with di- and tribromoacetaldehydes
The reaction of triphenyl phosphite and di- and tribromoacetaldehydes proceeds through initial halophilic attack with subsequent formation of triphenyl phosphate and tetraphenylphosphonium bromide. Β© 1989 Plenum Publishing Corporation
Tris(fluoroalkoxy)methylphosphonium salts in the synthesis of methylphosphoranes
The reactions of phosphites containing electron-withdrawing fluoroalkyl groups with methyl triflate gave tris(fluoroalkoxy)methylphosphonium triflates, which react with alcohols to give either tetrakis(fluoroalkoxy)methylphosphoranes (in the case of fluoroalcohols) or alkylation products - ethers and bis(fluoroalkoxy)methylphosphonates (in the case of unsubstituted alcohols). The structures of the phosphonium salts and phosphoranes were supported by1H and31P NMR spectroscopy. Β© 1991 Plenum Publishing Corporation
Reaction of 2-tert-butoxy-4,5-benzo-1,3,2-dioxaphospholane with tribromoacetaldehyde
The reaction of 2-tert-butoxy-4,5-benzo-1,3,2-dioxaphospholane with tribromo-acetaldehyde proceeds by initial halophilic attack on the bromine atom, leading to a product with retention of the P-Br bond (pyrocatechol bromophosphate) and an anion exchange product (pyrocatechol dibromovinylphosphate), and by initial attack at the carbon atom of the C=O group, which is accompanied by the elimination of isobutylene to form an Ξ±-hydroxyphosphonate. Β© 1990 Plenum Publishing Corporation
Synthesis of 1,4,2-dioxaphosphepanes by the reaction of 2-fluoroalkoxy-4-oxo-5,6-benzo-1,3,2-dioxaphosphorinanes with chloral
The reaction of 2-fluoroalkoxy-5,6-benzo-1,3,2-dioxaphosphorinanes with chloral leads to the formation of ring expansion products with a P-C bond, namely, 2-fluoroalkoxy-2,5-dioxo-3-trichloromethyl-6,7-benzo-1,4,2-dioxaphosphepanes with high stereoselectivity. Β© 1992 Plenum Publishing Corporation
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