Kvartära ammoniumsalter

Ammoniumsalter i vilka en kväveatom (med en +1 formell laddning) har fyra kol-kväve enkelbindningar; detta kväve skulle kunna bindas till fyra funktionella grupper innehållande kol.

1 – 15 av 170 Resultat

Kampanjer är tillgängliga

Tetrametylammoniumvätesulfat, 99+%, HPLC-kvalitet, Thermo Scientific Chemicals

CAS: 80526-82-5 Molekylformel: C₄H₁₃NO₄S Molekylvikt (g/mol): 171.21 MDL-nummer: MFCD00036149 InChI-nyckel: DWTYPCUOWWOADE-UHFFFAOYSA-M Synonym: tetramethylammonium hydrogen sulfate,tetramethylammonium bisulfate,tetramethylammonium hydrogen sulphate,tetramethylammonium hydrogensulfate,hydrogen sulfate; tetramethylazanium,methanaminium, n,n,n-trimethyl-, sulfate 1:1,hydrogen sulfate; tetramethylammonium,acmc-209pjn,ch3 4n hso4 .h2o,tetramethylammonium bisulfate solution PubChem CID: 157340 IUPAC-namn: vätesulfat;tetrametylazanium LEDER: C[N+](C)(C)C.OS(=O)(=O)[O-]

Prissättning och tillgänglighet
Specifikationer

Molekylformel	C₄H₁₃NO₄S
PubChem CID	157340
MDL-nummer	MFCD00036149
IUPAC-namn	vätesulfat;tetrametylazanium
CAS	80526-82-5
InChI-nyckel	DWTYPCUOWWOADE-UHFFFAOYSA-M
LEDER	C[N+](C)(C)C.OS(=O)(=O)[O-]
Molekylvikt (g/mol)	171.21
Synonym	tetramethylammonium hydrogen sulfate,tetramethylammonium bisulfate,tetramethylammonium hydrogen sulphate,tetramethylammonium hydrogensulfate,hydrogen sulfate; tetramethylazanium,methanaminium, n,n,n-trimethyl-, sulfate 1:1,hydrogen sulfate; tetramethylammonium,acmc-209pjn,ch3 4n hso4 .h2o,tetramethylammonium bisulfate solution

L-karnitin, 98+%, Thermo Scientific Chemicals

CAS: 541-15-1 Molekylformel: C7H15NO3 Molekylvikt (g/mol): 161.201 MDL-nummer: MFCD00038747 InChI-nyckel: PHIQHXFUZVPYII-ZCFIWIBFSA-N Synonym: l-carnitine,levocarnitine,vitamin bt,r-carnitine,carnitor,--carnitine,carnitine,--l-carnitine,karnitin,l---carnitine PubChem CID: 10917 ChEBI: CHEBI:16347 IUPAC-namn: (3R)-3-hydroxi-4-(trimetylazaniumyl)butanoat LEDER: C[N+](C)(C)CC(CC(=O)[O-])O

Prissättning och tillgänglighet
Specifikationer

Molekylformel	C7H15NO3
PubChem CID	10917
MDL-nummer	MFCD00038747
IUPAC-namn	(3R)-3-hydroxi-4-(trimetylazaniumyl)butanoat
CAS	541-15-1
InChI-nyckel	PHIQHXFUZVPYII-ZCFIWIBFSA-N
LEDER	C[N+](C)(C)CC(CC(=O)[O-])O
ChEBI	CHEBI:16347
Molekylvikt (g/mol)	161.201
Synonym	l-carnitine,levocarnitine,vitamin bt,r-carnitine,carnitor,--carnitine,carnitine,--l-carnitine,karnitin,l---carnitine

Kampanjer är tillgängliga

L(-)-karnitinhydroklorid, 98 %, Thermo Scientific Chemicals

Prissättning och tillgänglighet

Tetrametylammoniumhydroxidpentahydrat, 98 %, Thermo Scientific Chemicals

CAS: 10424-65-4 Molekylformel: C4H23NO6 Molekylvikt (g/mol): 181.23 MDL-nummer: MFCD00149566 InChI-nyckel: MYXKPFMQWULLOH-UHFFFAOYSA-M Synonym: tetramethylammonium hydroxide pentahydrate,b2hkt2lckq,unii-b2hkt2lckq,methanaminium, n,n,n-trimethyl-, hydroxide, pentahydrate,tmaoh,tetramethylammoniumhydroxid,tetrametanoamonio hydroxido,tetrametiloamonio hydroxido,methanaminium, n,n,n-trimethyl-, hydroxide, hydrate 1:1:5,acmc-2098bm PubChem CID: 82620 IUPAC-namn: tetrametylazan;hydroxid;pentahydrat LEDER: O.O.O.O.O.[OH-].C[N+](C)(C)C

Prissättning och tillgänglighet
Specifikationer

Molekylformel	C4H23NO6
PubChem CID	82620
MDL-nummer	MFCD00149566
IUPAC-namn	tetrametylazan;hydroxid;pentahydrat
CAS	10424-65-4
InChI-nyckel	MYXKPFMQWULLOH-UHFFFAOYSA-M
LEDER	O.O.O.O.O.[OH-].C[N+](C)(C)C
Molekylvikt (g/mol)	181.23
Synonym	tetramethylammonium hydroxide pentahydrate,b2hkt2lckq,unii-b2hkt2lckq,methanaminium, n,n,n-trimethyl-, hydroxide, pentahydrate,tmaoh,tetramethylammoniumhydroxid,tetrametanoamonio hydroxido,tetrametiloamonio hydroxido,methanaminium, n,n,n-trimethyl-, hydroxide, hydrate 1:1:5,acmc-2098bm

Tetrametylammoniumhydroxidpentahydrat, 98 %, Thermo Scientific Chemicals

Prissättning och tillgänglighet
Specifikationer

Molekylformel	C4H23NO6
PubChem CID	82620
MDL-nummer	MFCD00149566
IUPAC-namn	tetrametylazan;hydroxid;pentahydrat
CAS	10424-65-4
InChI-nyckel	MYXKPFMQWULLOH-UHFFFAOYSA-M
LEDER	O.O.O.O.O.[OH-].C[N+](C)(C)C
Molekylvikt (g/mol)	181.23
Synonym	tetramethylammonium hydroxide pentahydrate,b2hkt2lckq,unii-b2hkt2lckq,methanaminium, n,n,n-trimethyl-, hydroxide, pentahydrate,tmaoh,tetramethylammoniumhydroxid,tetrametanoamonio hydroxido,tetrametiloamonio hydroxido,methanaminium, n,n,n-trimethyl-, hydroxide, hydrate 1:1:5,acmc-2098bm

Tetrametylammoniumhydroxid, 10 % i vatten, Thermo Scientific Chemicals

CAS: 75-59-2 | C₄H₁₃NO | 91.15 g/mol

Prissättning och tillgänglighet
Specifikationer

Formel vikt	91.15
IUPAC-namn	tetrametylazan;hydroxid
InChI-nyckel	WGTYBPLFGIVFAS-UHFFFAOYSA-M
Hälsofara 3	GHS P Statement Do not breathe dust/fume/gas/mist/vapors/spray. Wear protective gloves/protective clothing/eye protection/face protection. IF SWALLOWED: rinse mouth. Do NOT induce vomiting. IF ON SKIN (or hair): Take off immediat
Hälsofara 2	GHS H Statement Harmful if swallowed. Toxic in contact with skin. Causes severe skin burns and eye damage.
Hälsofara 1	GHS-signalord: Fara
PubChem CID	60966
Förpackning	Plastflaska
Fieser	11,514
Linjär formel	(CH₃)₄NOH
Namnnotering	10% in Water
LEDER	C[N+](C)(C)C.[OH-]
RTECS-nummer	PA0875000
Molekylvikt (g/mol)	91.15
Molekylformel	C₄H₁₃NO
Densitet	1
MDL-nummer	MFCD00008280
Kokpunkt	100.0°C
Löslighetsinformation	Solubility in water: soluble.
Merck Index	15, 9371
Fysisk form	Vätska
Färg	Färglös
CAS	7732-18-5
EINECS-nummer	200-882-9
Synonym	tetramethylammonium hydroxide,tmah,hydroxyde de tetramethylammonium,nmw-w,nmd 3,tetramethyl ammonium hydroxide,unii-5gkp7317q2,ammonium, tetramethyl-, hydroxide,methanaminium, n,n,n-trimethyl-, hydroxide,tetramethylammoniumhydroxide
TSCA	TSCA
Kemiskt namn eller material	Tetramethylammonium hydroxide
Procent renhet	9.5 to 10.5%
Beilstein	04, 50

Hexadecyltrimetylammoniumklorid, 97 %, Thermo Scientific Chemicals

CAS: 112-02-7 Molekylformel: C19H42ClN Molekylvikt (g/mol): 320.00 MDL-nummer: MFCD00011773 InChI-nyckel: WOWHHFRSBJGXCM-UHFFFAOYSA-M Synonym: hexadecyltrimethylammonium chloride,cetrimonium chloride,cetyltrimethylammonium chloride,n,n,n-trimethylhexadecan-1-aminium chloride,dehyquart a,cetyl trimethyl ammonium chloride,aliquat 6,trimethylcetylammonium chloride,arquad 16-50,n-hexadecyltrimethylammonium chloride PubChem CID: 8154 ChEBI: CHEBI:53581 IUPAC-namn: hexadecyl(trimetyl)azanium;klorid LEDER: [Cl-].CCCCCCCCCCCCCCCC[N+](C)(C)C

Prissättning och tillgänglighet
Specifikationer

Molekylformel	C19H42ClN
PubChem CID	8154
MDL-nummer	MFCD00011773
IUPAC-namn	hexadecyl(trimetyl)azanium;klorid
CAS	112-02-7
InChI-nyckel	WOWHHFRSBJGXCM-UHFFFAOYSA-M
LEDER	[Cl-].CCCCCCCCCCCCCCCC[N+](C)(C)C
ChEBI	CHEBI:53581
Molekylvikt (g/mol)	320.00
Synonym	hexadecyltrimethylammonium chloride,cetrimonium chloride,cetyltrimethylammonium chloride,n,n,n-trimethylhexadecan-1-aminium chloride,dehyquart a,cetyl trimethyl ammonium chloride,aliquat 6,trimethylcetylammonium chloride,arquad 16-50,n-hexadecyltrimethylammonium chloride

Kampanjer är tillgängliga

Tetrabutylammoniumfosfat monobasiskt, 99 %, HPLC-kvalitet, Thermo Scientific Chemicals

CAS: 5574-97-0 Molekylformel: C16H38NO4P Molekylvikt (g/mol): 339.46 MDL-nummer: MFCD00064526 InChI-nyckel: ARRNBPCNZJXHRJ-UHFFFAOYSA-M Synonym: tetrabutylammonium dihydrogen phosphate,tetrabutylammonium phosphate,tetrabutylammonium dihydrogenphosphate,1-butanaminium, n,n,n-tributyl-, phosphate 1:1,tetra-n-butylammonium phosphate,tetrabutylazanium dihydrogen phosphate,dihydrogen phosphate; tetrabutylazanium,dihydrogen phosphate; tetrabutylammonium,tetrabutyl ammonium dihydrogen phosphate,tetrabutylammonium ion dihydrogenphosphate ion PubChem CID: 2735142 IUPAC-namn: divätefosfat;tetrabutylazanium LEDER: OP(O)([O-])=O.CCCC[N+](CCCC)(CCCC)CCCC

Prissättning och tillgänglighet
Specifikationer

Molekylformel	C16H38NO4P
PubChem CID	2735142
MDL-nummer	MFCD00064526
IUPAC-namn	divätefosfat;tetrabutylazanium
CAS	5574-97-0
InChI-nyckel	ARRNBPCNZJXHRJ-UHFFFAOYSA-M
LEDER	OP(O)([O-])=O.CCCC[N+](CCCC)(CCCC)CCCC
Molekylvikt (g/mol)	339.46
Synonym	tetrabutylammonium dihydrogen phosphate,tetrabutylammonium phosphate,tetrabutylammonium dihydrogenphosphate,1-butanaminium, n,n,n-tributyl-, phosphate 1:1,tetra-n-butylammonium phosphate,tetrabutylazanium dihydrogen phosphate,dihydrogen phosphate; tetrabutylazanium,dihydrogen phosphate; tetrabutylammonium,tetrabutyl ammonium dihydrogen phosphate,tetrabutylammonium ion dihydrogenphosphate ion

Tetraetylammoniumbromid, 99+%, Thermo Scientific Chemicals

CAS: 71-91-0 Molekylformel: C₈H₂₀BrN Molekylvikt (g/mol): 210.16 InChI-nyckel: HWCKGOZZJDHMNC-UHFFFAOYSA-M Synonym: tetraethylammonium bromide,teab,tea bromide,tetrylammonium bromide,sympatektoman,tetranium,etylon,bromethyl,beparon,etambro PubChem CID: 6285 IUPAC-namn: tetraetylazan;bromid LEDER: CC[N+](CC)(CC)CC.[Br-]

Prissättning och tillgänglighet
Specifikationer

Molekylformel	C₈H₂₀BrN
PubChem CID	6285
IUPAC-namn	tetraetylazan;bromid
CAS	71-91-0
InChI-nyckel	HWCKGOZZJDHMNC-UHFFFAOYSA-M
LEDER	CC[N+](CC)(CC)CC.[Br-]
Molekylvikt (g/mol)	210.16
Synonym	tetraethylammonium bromide,teab,tea bromide,tetrylammonium bromide,sympatektoman,tetranium,etylon,bromethyl,beparon,etambro

Kampanjer är tillgängliga

Bensyltrimetylammoniumklorid, 98+%, Thermo Scientific Chemicals

CAS: 56-93-9 Molekylformel: C10H16ClN Molekylvikt (g/mol): 185.70 MDL-nummer: MFCD00011782 InChI-nyckel: KXHPPCXNWTUNSB-UHFFFAOYSA-M Synonym: benzyltrimethylammonium chloride,tmbac,benzyl trimethylammonium chloride,benzyltrimethyl ammonium chloride,benzyl trimethyl ammonium chloride,benzenemethanaminium, n,n,n-trimethyl-, chloride,benzyltrimethylazanium chloride,unii-vnk45y7ba1,ammonium, benzyltrimethyl-, chloride,trimethylbenzylammonium chloride PubChem CID: 5963 IUPAC-namn: bensyl(trimetyl)azanium;klorid LEDER: [Cl-].C[N+](C)(C)CC1=CC=CC=C1

Prissättning och tillgänglighet
Specifikationer

Molekylformel	C10H16ClN
PubChem CID	5963
MDL-nummer	MFCD00011782
IUPAC-namn	bensyl(trimetyl)azanium;klorid
CAS	56-93-9
InChI-nyckel	KXHPPCXNWTUNSB-UHFFFAOYSA-M
LEDER	[Cl-].C[N+](C)(C)CC1=CC=CC=C1
Molekylvikt (g/mol)	185.70
Synonym	benzyltrimethylammonium chloride,tmbac,benzyl trimethylammonium chloride,benzyltrimethyl ammonium chloride,benzyl trimethyl ammonium chloride,benzenemethanaminium, n,n,n-trimethyl-, chloride,benzyltrimethylazanium chloride,unii-vnk45y7ba1,ammonium, benzyltrimethyl-, chloride,trimethylbenzylammonium chloride

Tetra-n-butylammoniumacetat, Thermo Scientific Chemicals

CAS: 10534-59-5 Molekylformel: C18H39NO2 Molekylvikt (g/mol): 301.52 MDL-nummer: MFCD00043208 InChI-nyckel: MCZDHTKJGDCTAE-UHFFFAOYSA-M Synonym: tetrabutylammonium acetate,1-butanaminium, n,n,n-tributyl-, acetate,tetra-n-butylammonium acetate,tetrabutylazanium acetate,tetrabutyl ammonium acetate,1-butanaminium, n,n,n-tributyl-, acetate 1:1,tetrabutylammonium ion acetate,2-phosphonooxy acrylic acid cyclohexylamine salt 1:1,n,n,n-tributylbutan-1-aminiumacetate,tetrabutylazanium ethanoate PubChem CID: 82707 IUPAC-namn: tetrabutylazanium;acetat LEDER: CC([O-])=O.CCCC[N+](CCCC)(CCCC)CCCC

Prissättning och tillgänglighet
Specifikationer

Molekylformel	C18H39NO2
PubChem CID	82707
MDL-nummer	MFCD00043208
IUPAC-namn	tetrabutylazanium;acetat
CAS	10534-59-5
InChI-nyckel	MCZDHTKJGDCTAE-UHFFFAOYSA-M
LEDER	CC([O-])=O.CCCC[N+](CCCC)(CCCC)CCCC
Molekylvikt (g/mol)	301.52
Synonym	tetrabutylammonium acetate,1-butanaminium, n,n,n-tributyl-, acetate,tetra-n-butylammonium acetate,tetrabutylazanium acetate,tetrabutyl ammonium acetate,1-butanaminium, n,n,n-tributyl-, acetate 1:1,tetrabutylammonium ion acetate,2-phosphonooxy acrylic acid cyclohexylamine salt 1:1,n,n,n-tributylbutan-1-aminiumacetate,tetrabutylazanium ethanoate

Tetrametylammoniumhydroxid, 25 % i vatten, Thermo Scientific Chemicals

CAS: 75-59-2 | C₄H₁₃NO | 91.15 g/mol

Prissättning och tillgänglighet
Specifikationer

Formel vikt	91.15
IUPAC-namn	tetrametylazan;hydroxid
InChI-nyckel	WGTYBPLFGIVFAS-UHFFFAOYSA-M
Hälsofara 3	GHS P Statement Wear protective gloves/protective clothing/eye protection/face protection. IF SWALLOWED: rinse mouth. Do NOT induce vomiting. Rinse mouth. IF IN EYES: Rinse cautiously with water for several minutes. Remove con
Hälsofara 2	GHS H Statement Causes severe skin burns and eye damage. Toxic if swallowed. Fatal in contact with skin. Causes damage to organs. Causes damage to organs through prolonged or repeated exposure. Toxic to aquatic life w
Hälsofara 1	GHS-signalord: Fara
PubChem CID	60966
Förpackning	Plastflaska
Fieser	11,514
Linjär formel	(CH₃)₄NOH
Namnnotering	25% in Water
LEDER	C[N+](C)(C)C.[OH-]
RTECS-nummer	PA0875000
Molekylvikt (g/mol)	91.15
Molekylformel	C₄H₁₃NO
Densitet	1.014
MDL-nummer	MFCD00008280
Brytningsindex	1.3780 to 1.3840 (20°C, 589nm)
Viskositet	3.13 mPa.s (19°C)
Kokpunkt	102.0°C
Löslighetsinformation	Solubility in water: soluble.
Merck Index	15,9371
Fysisk form	Lösning
Färg	Färglös till gul
Flampunkt	>95°C
Smältpunkt	-25.0°C
CAS	7732-18-5
EINECS-nummer	200-882-9
Synonym	tetramethylammonium hydroxide,tmah,hydroxyde de tetramethylammonium,nmw-w,nmd 3,tetramethyl ammonium hydroxide,unii-5gkp7317q2,ammonium, tetramethyl-, hydroxide,methanaminium, n,n,n-trimethyl-, hydroxide,tetramethylammoniumhydroxide
TSCA	TSCA
Kemiskt namn eller material	Tetramethylammonium hydroxide
Procent renhet	23 to 27%
Beilstein	04,5

Tetrametylammoniumhydroxidpentahydrat, 97 %, Thermo Scientific Chemicals

Prissättning och tillgänglighet
Specifikationer

Molekylformel	C4H23NO6
PubChem CID	82620
MDL-nummer	MFCD00149566
IUPAC-namn	tetrametylazan;hydroxid;pentahydrat
CAS	10424-65-4
InChI-nyckel	MYXKPFMQWULLOH-UHFFFAOYSA-M
LEDER	O.O.O.O.O.[OH-].C[N+](C)(C)C
Molekylvikt (g/mol)	181.23
Synonym	tetramethylammonium hydroxide pentahydrate,b2hkt2lckq,unii-b2hkt2lckq,methanaminium, n,n,n-trimethyl-, hydroxide, pentahydrate,tmaoh,tetramethylammoniumhydroxid,tetrametanoamonio hydroxido,tetrametiloamonio hydroxido,methanaminium, n,n,n-trimethyl-, hydroxide, hydrate 1:1:5,acmc-2098bm

Tetra-n-butylammoniumdivätetrifluorid, tech. 90 %, Thermo Scientific Chemicals

CAS: 99337-56-1 Molekylformel: C16H38F3N Molekylvikt (g/mol): 301.48 MDL-nummer: MFCD00145365 InChI-nyckel: MRXQMNWIADOAJY-UHFFFAOYSA-M Synonym: tetra-n-butylammonium dihydrogen trifluoride,tetra-n-butylammonium dihydrogentrifluoride,dihydrogen tetrabutylammonium fluoride,tetrabutylammonium dihydrogentrifluoride,tetrabutylammonium dihydrogen trifluoride,tetrabutylammonium fluoride dihydrofluoride,tetrabutylazanium fluoride dihydrofluoride,tetrabutylammoniumdihydrogentrifluoride,tetrabutylamonium dihydrogentrifluoride,tetrabutylammoniumdihydrogen trifluoride PubChem CID: 11748636 IUPAC-namn: tetrabutylazanium;fluorid;dihydrofluorid LEDER: F.F.[F-].CCCC[N+](CCCC)(CCCC)CCCC

Prissättning och tillgänglighet
Specifikationer

Molekylformel	C16H38F3N
PubChem CID	11748636
MDL-nummer	MFCD00145365
IUPAC-namn	tetrabutylazanium;fluorid;dihydrofluorid
CAS	99337-56-1
InChI-nyckel	MRXQMNWIADOAJY-UHFFFAOYSA-M
LEDER	F.F.[F-].CCCC[N+](CCCC)(CCCC)CCCC
Molekylvikt (g/mol)	301.48
Synonym	tetra-n-butylammonium dihydrogen trifluoride,tetra-n-butylammonium dihydrogentrifluoride,dihydrogen tetrabutylammonium fluoride,tetrabutylammonium dihydrogentrifluoride,tetrabutylammonium dihydrogen trifluoride,tetrabutylammonium fluoride dihydrofluoride,tetrabutylazanium fluoride dihydrofluoride,tetrabutylammoniumdihydrogentrifluoride,tetrabutylamonium dihydrogentrifluoride,tetrabutylammoniumdihydrogen trifluoride

Benzyldimethyl-n-tetradecylammonium chloride hydrate, 98%, Thermo Scientific Chemicals

CAS: 139-08-2 Molekylformel: C23H42ClN Molekylvikt (g/mol): 368.05 MDL-nummer: MFCD00011771 InChI-nyckel: OCBHHZMJRVXXQK-UHFFFAOYSA-M Synonym: miristalkonium chloride,n-benzyl-n,n-dimethyltetradecan-1-aminium chloride,zephiramine,benzyldimethyltetradecylammonium chloride,tetradecyldimethylbenzylammonium chloride,myristalkonium chloride,dibactol,faringets,quaternario 14b,sanibond 200lg PubChem CID: 8755 LEDER: [Cl-].CCCCCCCCCCCCCC[N+](C)(C)CC1=CC=CC=C1

Prissättning och tillgänglighet
Specifikationer

Molekylformel	C23H42ClN
PubChem CID	8755
MDL-nummer	MFCD00011771
CAS	139-08-2
InChI-nyckel	OCBHHZMJRVXXQK-UHFFFAOYSA-M
LEDER	[Cl-].CCCCCCCCCCCCCC[N+](C)(C)CC1=CC=CC=C1
Molekylvikt (g/mol)	368.05
Synonym	miristalkonium chloride,n-benzyl-n,n-dimethyltetradecan-1-aminium chloride,zephiramine,benzyldimethyltetradecylammonium chloride,tetradecyldimethylbenzylammonium chloride,myristalkonium chloride,dibactol,faringets,quaternario 14b,sanibond 200lg

FÖREG
1
2
3
4
5
6
...
12
NÄSTA

Kvartära ammoniumsalter

Filtrerade sökresultat

Begränsa resultat

Tetrametylammoniumvätesulfat, 99+%, HPLC-kvalitet, Thermo Scientific Chemicals Greener Choice ProductThis product offers one or more environmental benefits itemized in the U.S. FTC “Green Guides.”Learn More About the Greener Choice Program

Tetrabutylammoniumfosfat monobasiskt, 99 %, HPLC-kvalitet, Thermo Scientific Chemicals Greener Choice ProductThis product offers one or more environmental benefits itemized in the U.S. FTC “Green Guides.”Learn More About the Greener Choice Program

Tetrametylammoniumvätesulfat, 99+%, HPLC-kvalitet, Thermo Scientific Chemicals

Tetrabutylammoniumfosfat monobasiskt, 99 %, HPLC-kvalitet, Thermo Scientific Chemicals