ABCDE approach

Assess as you would on any medical ward, including ABCDE approach and checking allergies. Remember additional problems for psychiatric patients (Box 65.1). Involve the nurse if Roy s uncooperative, e.g. to demonstrate the examination or help him keep still. 

Conventional resuscitation guidelines should be followed scrupulously. Modern military experience has led to the development of the ABCDE approach (Box 3.5). 

In the synthesis of lumisterin steroid a D ABCD approach was used [151]. A key step is the Co-induced cyclization of cyclopentanoid ene-diynes prepared by thioalkylation of 2,3-substituted cyclopentanone zinc enolates with a-chlorosulfides. 

The cobalt-catalyzed [2+2+2] cycloaddition of 4-hydroxy-substituted enediynes [152] that has been implemented in the synthesis of 2-hydroxy substituted decahydrophenanthrenes [153] has shown that the hydroxy group in the propargyl position tolerates the chosen reaction conditions. So, this approach could be an appropriate route to hydrogenated trans-phenanthrenes, which are the ABC cores of ergosterin and lumisterin steroids. This was a reason to consider the diastereoselective synthesis of (3S)-hydroxyandrosta-5,7-diene-17-ones 2.307, the precursors of vitamin D, via a D ABCD approach. 

In this section, we shall examine the various approaches by which crown compounds that have their chiral elements associated in some way with fused ring systems can be constructed. A selection of the wide and growing range of saturated chiral diols—many of them derived finom readily available carbohydrates—which have been incorporated, as relatively inexpensive sources of chirality, into crown ether derivatives are displayed in Figure IS. It may be noted that the saturated chiral diols rely for their chirality on centers of the classical type (C abcd)—not so the chiral dihydroxy compounds associated with the unsaturated systems listed in Figure 16. These examples reveal that axes and planes of chirality join with less conventional chiral centers (C aaaa) in being sources of chirality in optically active crown ethers. 

In emergency stabilization, life-saving measures should always take priority over all other decontamination techniques. We have advocated the following approach ABCDE. 

The initial management of a patient with coma, seizures, or otherwise altered mental status should follow the same approach regardless of the poison involved. Attempting to make a specific toxicologic diagnosis only delays the application of supportive measures that form the basis ("ABCDs") of poisoning treatment. 

IV. Unsuccessful Approaches to Strychnine From ABCD Intermediates 371... 

We then set ont to attempt a more daring approach to forge the desired ABCD tetracycle. Inspection of mannal molecnlar models, and as seen in the inset in Scheme 16.5, a hydroxyl group at... 

When dealing with large populations of injured, you need to have an effective public address system so that your instructions can be heard by aU. In a chemical event, clear lanes that separate hot, warm, and cold decontamination zones are imperative. This needs to be appropriately staffed and equipped. The faster the victims can be separated from the contaminant, the better off they will be. Each victim needs to first be approached with rescuer safety and victim decontamination in mind, along with the Advanced Life Support ABCDEs for cardiac, trauma, and hazardous materials. If a toxidrome is found where an antidote exists, this should be started immediately when possible. After the victim is clean, then a secondary survey exam needs to be performed to look for the severity and distribution of injury with continuing care as appropriate. 

Using the chlorosilane approach, Iatrou and Hadjichristidis synthesized 3-miktoarm star terpolymers of the ABC type [232] and 4-miktoarm star copolymers and quaterpolymers of the A2B2 and ABCD type [233], respectively. The synthesis of the ABC star was based on the following reactions (Scheme 76). 

In the route just described (CD — ABCD), the bisannulation reagent 62 is the source of rings A and B. In an alternative, somewhat more involved, approach (D - BCD — ABCD Scheme 10), reagent 62 is the source of rings B and C. 

The Nicolaou group published a preliminary account of their synthesis in early 1994 (429) and followed this up with a series of full papers in 1995 430-433). The synthesis is of the form A+C— A-C ABC ABCD, and it is thus a convergent synthesis as opposed to the linear approach adopted by Holton. The C ring was prepared by a Diels-Alder reaction between diene 14.2.2 and dienophile 14.2.1, using phenylboronic acid as a tether to hold the reactants together. Elaboration of the adduct 14.2.3 then gave the protected ring C synthon 14.2.8. 

The Wender synthesis was reported in two communcations in 1997 435, 436), but the full papers have yet to appear. The synthesis is linear of the form A- AB- ABC- ABCD, but it is very different from the formally similar Holton approach. 

If the reaction is split into many small pieces, with cooling between each piece, then each reactor would traverse along a small segment on the boundary ABCDE in Eigure 7.26. As these sections are made smaller, we approach the structure of a differentially cooled reactor (DCR), and thus the candidate region boundary associated with the DCR is therefore given by an envelope of adiabatic PFR trajectories with different feed temperatures. 

Miktoarm polymers are essentially heteroarm star polymers where two or more arms of the star are chemically unique. Therefore, the same general approaches for the synthesis of star polymers also apply to miktoarms, with some additional constraints. Many research groups have sequentially performed orthogonal polymerization techniques to access a variety ABC and ABCD miktoarm polymers, in a core-first approach. 

Hence, area ABCD may be computed by integration of the curve s formula. An alternative approach is to draw the equivalent line AB, so that the cross-hatched areas are equal, from whence the rate efficiency is ... 

A method frequently used to compute an enthalpy change is to solve the CpdT integral graphically. This is shown schematically in Fig. 2-16, where the area ABCD represents the enthalpy change. The same approach can be used for entropy by plotting CpU vs T and then evaluating the area under the curve. 

New synthetic approaches to the ABCD ring systems of C-nor-D-homo-steroids have also been devised (see Figure 12). An A- to D-ring sequence by Brown and Lebreton uses hydrazone 167 (accessible from the classical Wieland—Miescher ketone, structure not shown) as a starting material. The C-ring was introduced via the aUylation of the corresponding hydra-zone with chloride 168, ozonolysis, aldol condensation, and olefin... 

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